diff --git a/src/if_python3.c b/src/if_python3.c
new file mode 100644
index 0000000..1d755e0
--- /dev/null
+++ b/src/if_python3.c
@@ -0,0 +1,2796 @@
+/* vi:set ts=8 sts=4 sw=4:
+ *
+ * VIM - Vi IMproved    by Bram Moolenaar
+ *
+ * Do ":help uganda"  in Vim to read copying and usage conditions.
+ * Do ":help credits" in Vim to see a list of people who contributed.
+ * See README.txt for an overview of the Vim source code.
+ */
+/*
+ * Python extensions by Paul Moore.
+ * Changes for Unix by David Leonard.
+ *
+ * This consists of four parts:
+ * 1. Python interpreter main program
+ * 2. Python output stream: writes output via [e]msg().
+ * 3. Implementation of the Vim module for Python
+ * 4. Utility functions for handling the interface between Vim and Python.
+ */
+
+/*
+ * Roland Puntaier 2009/sept/16:
+ * Adaptations to support both python3.x and python2.x
+ */
+
+// uncomment this if used with the debug version of python
+// #define Py_DEBUG
+
+#include "vim.h"
+
+#include <limits.h>
+
+/* Python.h defines _POSIX_THREADS itself (if needed) */
+#ifdef _POSIX_THREADS
+# undef _POSIX_THREADS
+#endif
+
+#if defined(_WIN32) && defined (HAVE_FCNTL_H)
+# undef HAVE_FCNTL_H
+#endif
+
+#ifdef _DEBUG
+# undef _DEBUG
+#endif
+
+#ifdef HAVE_STDARG_H
+# undef HAVE_STDARG_H   /* Python's config.h defines it as well. */
+#endif
+
+#define PY_SSIZE_T_CLEAN
+
+#ifdef F_BLANK
+# undef F_BLANK
+#endif
+
+#ifdef _POSIX_C_SOURCE  /* defined in feature.h */
+# undef _POSIX_C_SOURCE
+#endif
+
+#include <Python.h>
+#if defined(MACOS) && !defined(MACOS_X_UNIX)
+# include "macglue.h"
+# include <CodeFragments.h>
+#endif
+#undef main /* Defined in python.h - aargh */
+#undef HAVE_FCNTL_H /* Clash with os_win32.h */
+
+static void init_structs(void);
+
+#if defined(DYNAMIC_PYTHON3)
+
+#ifndef _WIN32
+#include <dlfcn.h>
+#define FARPROC void*
+#define HINSTANCE void*
+#define load_dll(n) dlopen((n),RTLD_LAZY)
+#define close_dll dlclose
+#define symbol_from_dll dlsym
+#else
+#define load_dll LoadLibrary
+#define close_dll FreeLibrary
+#define symbol_from_dll GetProcAddress
+#endif
+/*
+ * Wrapper defines
+ */
+#undef PyArg_Parse
+# define PyArg_Parse py3_PyArg_Parse
+#undef PyArg_ParseTuple
+# define PyArg_ParseTuple py3_PyArg_ParseTuple
+# define PyDict_SetItemString py3_PyDict_SetItemString
+# define PyErr_BadArgument py3_PyErr_BadArgument
+# define PyErr_Clear py3_PyErr_Clear
+# define PyErr_NoMemory py3_PyErr_NoMemory
+# define PyErr_Occurred py3_PyErr_Occurred
+# define PyErr_SetNone py3_PyErr_SetNone
+# define PyErr_SetString py3_PyErr_SetString
+# define PyEval_InitThreads py3_PyEval_InitThreads
+# define PyEval_RestoreThread py3_PyEval_RestoreThread
+# define PyEval_SaveThread py3_PyEval_SaveThread
+# define PyGILState_Ensure py3_PyGILState_Ensure
+# define PyGILState_Release py3_PyGILState_Release
+# define PyLong_AsLong py3_PyLong_AsLong
+# define PyLong_FromLong py3_PyLong_FromLong
+# define PyList_GetItem py3_PyList_GetItem
+# define PyList_Append py3_PyList_Append
+# define PyList_New py3_PyList_New
+# define PyList_SetItem py3_PyList_SetItem
+# define PyList_Size py3_PyList_Size
+# define PySlice_GetIndicesEx py3_PySlice_GetIndicesEx
+# define PyImport_ImportModule py3_PyImport_ImportModule
+# define PyObject_Init py3__PyObject_Init
+# define PyDict_New py3_PyDict_New
+# define PyDict_GetItemString py3_PyDict_GetItemString
+# define PyModule_GetDict py3_PyModule_GetDict
+#undef PyRun_SimpleString
+# define PyRun_SimpleString py3_PyRun_SimpleString
+# define PySys_SetObject py3_PySys_SetObject
+# define PySys_SetArgv py3_PySys_SetArgv
+# define PyType_Type (*py3_PyType_Type)
+# define PyType_Ready py3_PyType_Ready
+#undef Py_BuildValue
+# define Py_BuildValue py3_Py_BuildValue
+# define Py_Initialize py3_Py_Initialize
+# define Py_Finalize py3_Py_Finalize
+# define Py_IsInitialized py3_Py_IsInitialized
+# define _Py_NoneStruct (*py3__Py_NoneStruct)
+# define PyModule_AddObject py3_PyModule_AddObject
+# define PyImport_AppendInittab py3_PyImport_AppendInittab
+# define _PyUnicode_AsString py3__PyUnicode_AsString
+# define PyObject_GenericGetAttr py3_PyObject_GenericGetAttr
+# define PySlice_Type (*py3_PySlice_Type)
+#ifdef Py_DEBUG
+    # define _Py_NegativeRefcount py3__Py_NegativeRefcount
+    # define _Py_RefTotal (*py3__Py_RefTotal)
+    # define _Py_Dealloc py3__Py_Dealloc
+    # define _PyObject_DebugMalloc py3__PyObject_DebugMalloc
+    # define _PyObject_DebugFree py3__PyObject_DebugFree
+#else
+    # define PyObject_Malloc py3_PyObject_Malloc
+    # define PyObject_Free py3_PyObject_Free
+#endif
+# define PyType_GenericAlloc py3_PyType_GenericAlloc
+# define PyType_GenericNew py3_PyType_GenericNew
+# define PyModule_Create2 py3_PyModule_Create2
+#undef PyUnicode_FromString
+# define PyUnicode_FromString py3_PyUnicode_FromString
+#undef PyUnicode_FromStringAndSize
+# define PyUnicode_FromStringAndSize py3_PyUnicode_FromStringAndSize
+
+#ifdef Py_DEBUG
+#undef PyObject_NEW
+#define PyObject_NEW(type, typeobj) \
+( (type *) PyObject_Init( \
+        (PyObject *) _PyObject_DebugMalloc( _PyObject_SIZE(typeobj) ), (typeobj)) )
+#endif
+/*
+ * Pointers for dynamic link
+ */
+static int (*py3_PySys_SetArgv)(int, wchar_t **);
+static void (*py3_Py_Initialize)(void);
+static PyObject* (*py3_PyList_New)(Py_ssize_t size);
+static PyGILState_STATE (*py3_PyGILState_Ensure)(void);
+static void (*py3_PyGILState_Release)(PyGILState_STATE);
+static int (*py3_PySys_SetObject)(char *, PyObject *);
+static PyObject* (*py3_PyList_Append)(PyObject *, PyObject *);
+static Py_ssize_t (*py3_PyList_Size)(PyObject *);
+static int (*py3_PySlice_GetIndicesEx)(PySliceObject *r, Py_ssize_t length,
+                     Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step, Py_ssize_t *slicelength);
+static PyObject* (*py3_PyErr_NoMemory)(void);
+static void (*py3_Py_Finalize)(void);
+static void (*py3_PyErr_SetString)(PyObject *, const char *);
+static int (*py3_PyRun_SimpleString)(char *);
+static PyObject* (*py3_PyList_GetItem)(PyObject *, Py_ssize_t);
+static PyObject* (*py3_PyImport_ImportModule)(const char *);
+static int (*py3_PyErr_BadArgument)(void);
+static PyTypeObject* py3_PyType_Type;
+static PyObject* (*py3_PyErr_Occurred)(void);
+static PyObject* (*py3_PyModule_GetDict)(PyObject *);
+static int (*py3_PyList_SetItem)(PyObject *, Py_ssize_t, PyObject *);
+static PyObject* (*py3_PyDict_GetItemString)(PyObject *, const char *);
+static PyObject* (*py3_PyLong_FromLong)(long);
+static PyObject* (*py3_PyDict_New)(void);
+static PyObject* (*py3_Py_BuildValue)(char *, ...);
+static int (*py3_PyType_Ready)(PyTypeObject *type);
+static int (*py3_PyDict_SetItemString)(PyObject *dp, char *key, PyObject *item);
+static PyObject* (*py3_PyUnicode_FromString)(const char *u);
+static PyObject* (*py3_PyUnicode_FromStringAndSize)(const char *u, Py_ssize_t size);
+static long (*py3_PyLong_AsLong)(PyObject *);
+static void (*py3_PyErr_SetNone)(PyObject *);
+static void (*py3_PyEval_InitThreads)(void);
+static void(*py3_PyEval_RestoreThread)(PyThreadState *);
+static PyThreadState*(*py3_PyEval_SaveThread)(void);
+static int (*py3_PyArg_Parse)(PyObject *, char *, ...);
+static int (*py3_PyArg_ParseTuple)(PyObject *, char *, ...);
+static int (*py3_Py_IsInitialized)(void);
+static void (*py3_PyErr_Clear)(void);
+static PyObject*(*py3__PyObject_Init)(PyObject *, PyTypeObject *);
+static PyObject* py3__Py_NoneStruct;
+static int (*py3_PyModule_AddObject)(PyObject *m, const char *name, PyObject *o);
+static int (*py3_PyImport_AppendInittab)(const char *name, PyObject* (*initfunc)(void));
+static char* (*py3__PyUnicode_AsString)(PyObject *unicode);
+static PyObject* (*py3_PyObject_GenericGetAttr)(PyObject *obj, PyObject *name);
+static PyObject* (*py3_PyModule_Create2)(struct PyModuleDef* module, int module_api_version);
+static PyObject* (*py3_PyType_GenericAlloc)(PyTypeObject *type, Py_ssize_t nitems);
+static PyObject* (*py3_PyType_GenericNew)(PyTypeObject *type, PyObject *args, PyObject *kwds);
+static PyTypeObject* py3_PySlice_Type;
+#ifdef Py_DEBUG
+    static void (*py3__Py_NegativeRefcount)(const char *fname, int lineno, PyObject *op);
+    static Py_ssize_t* py3__Py_RefTotal;
+    static void (*py3__Py_Dealloc)(PyObject *obj);
+    static void (*py3__PyObject_DebugFree)(void*);
+    static void* (*py3__PyObject_DebugMalloc)(size_t);
+#else
+    static void (*py3_PyObject_Free)(void*);
+    static void* (*py3_PyObject_Malloc)(size_t);
+#endif
+
+static HINSTANCE hinstPy3 = 0; /* Instance of python.dll */
+
+/* Imported exception objects */
+static PyObject *p3imp_PyExc_AttributeError;
+static PyObject *p3imp_PyExc_IndexError;
+static PyObject *p3imp_PyExc_KeyboardInterrupt;
+static PyObject *p3imp_PyExc_TypeError;
+static PyObject *p3imp_PyExc_ValueError;
+
+# define PyExc_AttributeError p3imp_PyExc_AttributeError
+# define PyExc_IndexError p3imp_PyExc_IndexError
+# define PyExc_KeyboardInterrupt p3imp_PyExc_KeyboardInterrupt
+# define PyExc_TypeError p3imp_PyExc_TypeError
+# define PyExc_ValueError p3imp_PyExc_ValueError
+
+/*
+ * Table of name to function pointer of python.
+ */
+# define PYTHON_PROC FARPROC
+static struct
+{
+    char *name;
+    PYTHON_PROC *ptr;
+} py3_funcname_table[] =
+{
+    {"PySys_SetArgv", (PYTHON_PROC*)&py3_PySys_SetArgv},
+    {"Py_Initialize", (PYTHON_PROC*)&py3_Py_Initialize},
+    {"PyArg_ParseTuple", (PYTHON_PROC*)&py3_PyArg_ParseTuple},
+    {"PyList_New", (PYTHON_PROC*)&py3_PyList_New},
+    {"PyGILState_Ensure", (PYTHON_PROC*)&py3_PyGILState_Ensure},
+    {"PyGILState_Release", (PYTHON_PROC*)&py3_PyGILState_Release},
+    {"PySys_SetObject", (PYTHON_PROC*)&py3_PySys_SetObject},
+    {"PyList_Append", (PYTHON_PROC*)&py3_PyList_Append},
+    {"PyList_Size", (PYTHON_PROC*)&py3_PyList_Size},
+    {"PySlice_GetIndicesEx", (PYTHON_PROC*)&py3_PySlice_GetIndicesEx},
+    {"PyErr_NoMemory", (PYTHON_PROC*)&py3_PyErr_NoMemory},
+    {"Py_Finalize", (PYTHON_PROC*)&py3_Py_Finalize},
+    {"PyErr_SetString", (PYTHON_PROC*)&py3_PyErr_SetString},
+    {"PyRun_SimpleString", (PYTHON_PROC*)&py3_PyRun_SimpleString},
+    {"PyList_GetItem", (PYTHON_PROC*)&py3_PyList_GetItem},
+    {"PyImport_ImportModule", (PYTHON_PROC*)&py3_PyImport_ImportModule},
+    {"PyErr_BadArgument", (PYTHON_PROC*)&py3_PyErr_BadArgument},
+    {"PyType_Type", (PYTHON_PROC*)&py3_PyType_Type},
+    {"PyErr_Occurred", (PYTHON_PROC*)&py3_PyErr_Occurred},
+    {"PyModule_GetDict", (PYTHON_PROC*)&py3_PyModule_GetDict},
+    {"PyList_SetItem", (PYTHON_PROC*)&py3_PyList_SetItem},
+    {"PyDict_GetItemString", (PYTHON_PROC*)&py3_PyDict_GetItemString},
+    {"PyLong_FromLong", (PYTHON_PROC*)&py3_PyLong_FromLong},
+    {"PyDict_New", (PYTHON_PROC*)&py3_PyDict_New},
+    {"Py_BuildValue", (PYTHON_PROC*)&py3_Py_BuildValue},
+    {"PyType_Ready", (PYTHON_PROC*)&py3_PyType_Ready},
+    {"PyDict_SetItemString", (PYTHON_PROC*)&py3_PyDict_SetItemString},
+    {"PyLong_AsLong", (PYTHON_PROC*)&py3_PyLong_AsLong},
+    {"PyErr_SetNone", (PYTHON_PROC*)&py3_PyErr_SetNone},
+    {"PyEval_InitThreads", (PYTHON_PROC*)&py3_PyEval_InitThreads},
+    {"PyEval_RestoreThread", (PYTHON_PROC*)&py3_PyEval_RestoreThread},
+    {"PyEval_SaveThread", (PYTHON_PROC*)&py3_PyEval_SaveThread},
+    {"PyArg_Parse", (PYTHON_PROC*)&py3_PyArg_Parse},
+    {"PyArg_ParseTuple", (PYTHON_PROC*)&py3_PyArg_ParseTuple},
+    {"Py_IsInitialized", (PYTHON_PROC*)&py3_Py_IsInitialized},
+    {"_Py_NoneStruct", (PYTHON_PROC*)&py3__Py_NoneStruct},
+    {"PyErr_Clear", (PYTHON_PROC*)&py3_PyErr_Clear},
+    {"PyObject_Init", (PYTHON_PROC*)&py3__PyObject_Init},
+    {"PyModule_AddObject", (PYTHON_PROC*)&py3_PyModule_AddObject},
+    {"PyImport_AppendInittab", (PYTHON_PROC*)&py3_PyImport_AppendInittab},
+    {"_PyUnicode_AsString", (PYTHON_PROC*)&py3__PyUnicode_AsString},
+    {"PyObject_GenericGetAttr", (PYTHON_PROC*)&py3_PyObject_GenericGetAttr},
+    {"PyModule_Create2", (PYTHON_PROC*)&py3_PyModule_Create2},
+    {"PyType_GenericAlloc", (PYTHON_PROC*)&py3_PyType_GenericAlloc},
+    {"PyType_GenericNew", (PYTHON_PROC*)&py3_PyType_GenericNew},
+    {"PySlice_Type", (PYTHON_PROC*)&py3_PySlice_Type},
+#ifdef Py_DEBUG
+    {"_Py_NegativeRefcount", (PYTHON_PROC*)&py3__Py_NegativeRefcount},
+    {"_Py_RefTotal", (PYTHON_PROC*)&py3__Py_RefTotal},
+    {"_Py_Dealloc", (PYTHON_PROC*)&py3__Py_Dealloc},
+    {"_PyObject_DebugFree", (PYTHON_PROC*)&py3__PyObject_DebugFree},
+    {"_PyObject_DebugMalloc", (PYTHON_PROC*)&py3__PyObject_DebugMalloc},
+#else
+    {"PyObject_Malloc", (PYTHON_PROC*)&py3_PyObject_Malloc},
+    {"PyObject_Free", (PYTHON_PROC*)&py3_PyObject_Free},
+#endif
+    {"", NULL},
+};
+
+/*
+ * Free python.dll
+ */
+static void end_dynamic_python3(void)
+{
+    if (hinstPy3)
+    {
+        close_dll(hinstPy3);
+        hinstPy3 = 0;
+    }
+}
+
+/*
+ * Load library and get all pointers.
+ * Parameter 'libname' provides name of DLL.
+ * Return OK or FAIL.
+ */
+static int py3_runtime_link_init(char *libname, int verbose)
+{
+    int i;
+
+    if (hinstPy3)
+        return OK;
+    hinstPy3 = load_dll(libname);
+
+    if (!hinstPy3)
+    {
+        if (verbose)
+            EMSG2(_(e_loadlib), libname);
+        return FAIL;
+    }
+
+    for (i = 0; py3_funcname_table[i].ptr; ++i)
+    {
+        if ((*py3_funcname_table[i].ptr = symbol_from_dll(hinstPy3,
+                        py3_funcname_table[i].name)) == NULL)
+        {
+            close_dll(hinstPy3);
+            hinstPy3 = 0;
+            if (verbose)
+                EMSG2(_(e_loadfunc), py3_funcname_table[i].name);
+            return FAIL;
+        }
+    }
+
+    /* load unicode functions separately as only the ucs2 or the ucs4 functions
+     * will be present in the library
+     */
+    void *ucs_from_string, *ucs_from_string_and_size;
+
+    ucs_from_string = symbol_from_dll(hinstPy3, "PyUnicodeUCS2_FromString");
+    ucs_from_string_and_size = symbol_from_dll(hinstPy3,
+            "PyUnicodeUCS2_FromStringAndSize");
+    if (!ucs_from_string || !ucs_from_string_and_size)
+    {
+        ucs_from_string = symbol_from_dll(hinstPy3,
+                "PyUnicodeUCS4_FromString");
+        ucs_from_string_and_size = symbol_from_dll(hinstPy3,
+                "PyUnicodeUCS4_FromStringAndSize");
+    }
+    if (ucs_from_string && ucs_from_string_and_size)
+    {
+        py3_PyUnicode_FromString = ucs_from_string;
+        py3_PyUnicode_FromStringAndSize = ucs_from_string_and_size;
+    }
+    else
+    {
+        close_dll(hinstPy3);
+        hinstPy3 = 0;
+        if (verbose)
+            EMSG2(_(e_loadfunc), "PyUnicode_UCSX_*");
+        return FAIL;
+    }
+
+    return OK;
+}
+
+/*
+ * If python is enabled (there is installed python on Windows system) return
+ * TRUE, else FALSE.
+ */
+int python3_enabled(int verbose)
+{
+    return py3_runtime_link_init(DYNAMIC_PYTHON3_DLL, verbose) == OK;
+}
+
+/* Load the standard Python exceptions - don't import the symbols from the
+ * DLL, as this can cause errors (importing data symbols is not reliable).
+ */
+static void get_py3_exceptions __ARGS((void));
+
+static void get_py3_exceptions()
+{
+    PyObject *exmod = PyImport_ImportModule("builtins");
+    PyObject *exdict = PyModule_GetDict(exmod);
+    p3imp_PyExc_AttributeError = PyDict_GetItemString(exdict, "AttributeError");
+    p3imp_PyExc_IndexError = PyDict_GetItemString(exdict, "IndexError");
+    p3imp_PyExc_KeyboardInterrupt = PyDict_GetItemString(exdict, "KeyboardInterrupt");
+    p3imp_PyExc_TypeError = PyDict_GetItemString(exdict, "TypeError");
+    p3imp_PyExc_ValueError = PyDict_GetItemString(exdict, "ValueError");
+    Py_XINCREF(p3imp_PyExc_AttributeError);
+    Py_XINCREF(p3imp_PyExc_IndexError);
+    Py_XINCREF(p3imp_PyExc_KeyboardInterrupt);
+    Py_XINCREF(p3imp_PyExc_TypeError);
+    Py_XINCREF(p3imp_PyExc_ValueError);
+    Py_XDECREF(exmod);
+}
+#endif /* DYNAMIC_PYTHON3 */
+
+static void call_PyObject_Free(void *p)
+{
+#ifdef Py_DEBUG
+    _PyObject_DebugFree(p);
+#else
+    PyObject_Free(p);
+#endif
+}
+static PyObject* call_PyType_GenericNew(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+    return PyType_GenericNew(type,args,kwds);
+}
+static PyObject* call_PyType_GenericAlloc(PyTypeObject *type, Py_ssize_t nitems)
+{
+    return PyType_GenericAlloc(type,nitems);
+}
+
+/******************************************************
+ * Internal function prototypes.
+ */
+
+static void DoPy3Command(exarg_T *, const char *);
+static Py_ssize_t RangeStart;
+static Py_ssize_t RangeEnd;
+
+static void PythonIO_Flush(void);
+static int PythonIO_Init(void);
+static void PythonIO_Fini(void);
+PyMODINIT_FUNC Py3Init_vim(void);
+
+/* Utility functions for the vim/python interface
+ * ----------------------------------------------
+ */
+static PyObject *GetBufferLine(buf_T *, Py_ssize_t);
+
+static int SetBufferLine(buf_T *, Py_ssize_t, PyObject *, Py_ssize_t*);
+static int InsertBufferLines(buf_T *, Py_ssize_t, PyObject *, Py_ssize_t*);
+static PyObject *GetBufferLineList(buf_T *buf, Py_ssize_t lo, Py_ssize_t hi);
+
+static PyObject *LineToString(const char *);
+static char *StringToLine(PyObject *);
+
+static int VimErrorCheck(void);
+
+#define PyErr_SetVim(str) PyErr_SetString(VimError, str)
+
+/******************************************************
+ * 1. Python interpreter main program.
+ */
+
+static int py3initialised = 0;
+
+
+static PyGILState_STATE pygilstate = PyGILState_UNLOCKED;
+
+/*
+ * obtain a lock on the Vim data structures
+ */
+static void Python_Lock_Vim(void)
+{
+}
+
+/*
+ * release a lock on the Vim data structures
+ */
+static void Python_Release_Vim(void)
+{
+}
+
+void python3_end()
+{
+    static int recurse = 0;
+
+    /* If a crash occurs while doing this, don't try again. */
+    if (recurse != 0)
+        return;
+
+    ++recurse;
+
+#ifdef DYNAMIC_PYTHON3
+    if (hinstPy3)
+#endif
+    if (Py_IsInitialized())
+    {
+	// acquire lock before finalizing
+	pygilstate = PyGILState_Ensure();
+
+        PythonIO_Fini();
+        Py_Finalize();
+    }
+
+#ifdef DYNAMIC_PYTHON3
+    end_dynamic_python3();
+#endif
+
+    --recurse;
+}
+
+static int Python3_Init(void)
+{
+    if (!py3initialised)
+    {
+#ifdef DYNAMIC_PYTHON3
+        if (!python3_enabled(TRUE))
+        {
+            EMSG(_("E263: Sorry, this command is disabled, the Python library could not be loaded."));
+            goto fail;
+        }
+#endif
+
+	init_structs();
+
+        /* initialise threads */
+        PyEval_InitThreads();
+
+#if !defined(MACOS) || defined(MACOS_X_UNIX)
+        Py_Initialize();
+#else
+        PyMac_Initialize();
+#endif
+
+#ifdef DYNAMIC_PYTHON3
+        get_py3_exceptions();
+#endif
+
+        if (PythonIO_Init())
+            goto fail;
+
+        PyImport_AppendInittab("vim", Py3Init_vim);
+
+        /* Remove the element from sys.path that was added because of our
+         * argv[0] value in Py3Init_vim().  Previously we used an empty
+         * string, but dependinding on the OS we then get an empty entry or
+         * the current directory in sys.path. */
+        PyRun_SimpleString("import sys; sys.path = list(filter(lambda x: x != '/must>not&exist', sys.path))");
+
+	// lock is created and acquired in PyEval_InitThreads() and thread
+	// state is created in Py_Initialize()
+	// there _PyGILState_NoteThreadState() also sets gilcounter to 1
+	// (python must have threads enabled!)
+	// so the following does both: unlock GIL and save thread state in TLS
+	// without deleting thread state
+	PyGILState_Release(pygilstate);
+
+        py3initialised = 1;
+    }
+
+    return 0;
+
+fail:
+    /* We call PythonIO_Flush() here to print any Python errors.
+     * This is OK, as it is possible to call this function even
+     * if PythonIO_Init() has not completed successfully (it will
+     * not do anything in this case).
+     */
+    PythonIO_Flush();
+    return -1;
+}
+
+/*
+ * External interface
+ */
+static void DoPy3Command(exarg_T *eap, const char *cmd)
+{
+#if defined(MACOS) && !defined(MACOS_X_UNIX)
+    GrafPtr             oldPort;
+#endif
+#if defined(HAVE_LOCALE_H) || defined(X_LOCALE)
+    char                *saved_locale;
+#endif
+
+#if defined(MACOS) && !defined(MACOS_X_UNIX)
+    GetPort(&oldPort);
+    /* Check if the Python library is available */
+    if ((Ptr)PyMac_Initialize == (Ptr)kUnresolvedCFragSymbolAddress)
+        goto theend;
+#endif
+    if (Python3_Init())
+        goto theend;
+
+    RangeStart = eap->line1;
+    RangeEnd = eap->line2;
+    Python_Release_Vim();           /* leave vim */
+
+#if defined(HAVE_LOCALE_H) || defined(X_LOCALE)
+    /* Python only works properly when the LC_NUMERIC locale is "C". */
+    saved_locale = setlocale(LC_NUMERIC, NULL);
+    if (saved_locale == NULL || STRCMP(saved_locale, "C") == 0)
+        saved_locale = NULL;
+    else
+    {
+        /* Need to make a copy, value may change when setting new locale. */
+        saved_locale = (char *)vim_strsave((char_u *)saved_locale);
+        (void)setlocale(LC_NUMERIC, "C");
+    }
+#endif
+
+    pygilstate = PyGILState_Ensure();
+
+    PyRun_SimpleString((char *)(cmd));
+
+    PyGILState_Release(pygilstate);
+
+#if defined(HAVE_LOCALE_H) || defined(X_LOCALE)
+    if (saved_locale != NULL)
+    {
+        (void)setlocale(LC_NUMERIC, saved_locale);
+        vim_free(saved_locale);
+    }
+#endif
+
+    Python_Lock_Vim();              /* enter vim */
+    PythonIO_Flush();
+#if defined(MACOS) && !defined(MACOS_X_UNIX)
+    SetPort(oldPort);
+#endif
+
+theend:
+    return;         /* keeps lint happy */
+}
+
+/*
+ * ":python"
+ */
+void ex_python3(exarg_T *eap)
+{
+    char_u *script;
+
+    script = script_get(eap, eap->arg);
+    if (!eap->skip)
+    {
+        if (script == NULL)
+            DoPy3Command(eap, (char *)eap->arg);
+        else
+            DoPy3Command(eap, (char *)script);
+    }
+    vim_free(script);
+}
+
+#define BUFFER_SIZE 2048
+
+/*
+ * ":pyfile"
+ */
+    void
+ex_py3file(exarg_T *eap)
+{
+    static char buffer[BUFFER_SIZE];
+    const char *file;
+    char *p;
+    int i;
+
+    /* Have to do it like this. PyRun_SimpleFile requires you to pass a
+     * stdio file pointer, but Vim and the Python DLL are compiled with
+     * different options under Windows, meaning that stdio pointers aren't
+     * compatible between the two. Yuk.
+     *
+     * construct: exec(compile(open('a_filename').read(), 'a_filename', 'exec'))
+     *
+     * We need to escape any backslashes or single quotes in the file name, so that
+     * Python won't mangle the file name.
+     */
+
+    strcpy(buffer, "exec(compile(open('");
+    p = buffer + 19; /* size of "exec(compile(open('" */
+
+    for (i=0; i<2; ++i)
+    {
+        file = (char *)eap->arg;
+        while (*file && p < buffer + (BUFFER_SIZE - 3))
+        {
+            if (*file == '\\' || *file == '\'')
+                *p++ = '\\';
+            *p++ = *file++;
+        }
+        /* If we didn't finish the file name, we hit a buffer overflow */
+        if (*file != '\0')
+            return;
+        if (i==0)
+        {
+            strcpy(p,"').read(),'");
+            p += 11;
+        }
+        else
+        {
+            strcpy(p,"','exec'))");
+            p += 10;
+        }
+    }
+
+
+    /* Execute the file */
+    DoPy3Command(eap, buffer);
+}
+
+/******************************************************
+ * 2. Python output stream: writes output via [e]msg().
+ */
+
+/* Implementation functions
+ */
+
+static PyObject *OutputGetattro(PyObject *, PyObject *);
+static int OutputSetattro(PyObject *, PyObject *, PyObject *);
+
+static PyObject *OutputWrite(PyObject *, PyObject *);
+static PyObject *OutputWritelines(PyObject *, PyObject *);
+
+typedef void (*writefn)(char_u *);
+static void writer(writefn fn, char_u *str, Py_ssize_t n);
+
+/* Output object definition
+ */
+
+typedef struct
+{
+    PyObject_HEAD
+    long softspace;
+    long error;
+} OutputObject;
+
+static struct PyMethodDef OutputMethods[] = {
+    /* name,        function,           calling,    documentation */
+    {"write",       OutputWrite,        1,          "" },
+    {"writelines",  OutputWritelines,   1,          "" },
+    { NULL,         NULL,               0,          NULL }
+};
+
+static PyTypeObject OutputType;
+
+/*************/
+
+static PyObject * OutputGetattro(PyObject *self, PyObject *nameobj)
+{
+    char *name = "";
+    if (PyUnicode_Check(nameobj))
+        name = _PyUnicode_AsString(nameobj);
+
+    if (strcmp(name, "softspace") == 0)
+        return PyLong_FromLong(((OutputObject *)(self))->softspace);
+
+    return PyObject_GenericGetAttr(self, nameobj);
+}
+
+static int OutputSetattro(PyObject *self, PyObject *nameobj, PyObject *val)
+{
+    char *name = "";
+    if (PyUnicode_Check(nameobj))
+        name = _PyUnicode_AsString(nameobj);
+
+    if (val == NULL) {
+        PyErr_SetString(PyExc_AttributeError, _("can't delete OutputObject attributes"));
+        return -1;
+    }
+
+    if (strcmp(name, "softspace") == 0)
+    {
+        if (!PyLong_Check(val)) {
+            PyErr_SetString(PyExc_TypeError, _("softspace must be an integer"));
+            return -1;
+        }
+
+        ((OutputObject *)(self))->softspace = PyLong_AsLong(val);
+        return 0;
+    }
+
+    PyErr_SetString(PyExc_AttributeError, _("invalid attribute"));
+    return -1;
+}
+
+/*************/
+
+static PyObject * OutputWrite(PyObject *self, PyObject *args)
+{
+    int len;
+    char *str;
+    int error = ((OutputObject *)(self))->error;
+
+    if (!PyArg_ParseTuple(args, "s#", &str, &len))
+        return NULL;
+
+    Py_BEGIN_ALLOW_THREADS
+    Python_Lock_Vim();
+    writer((writefn)(error ? emsg : msg), (char_u *)str, len);
+    Python_Release_Vim();
+    Py_END_ALLOW_THREADS
+
+    Py_INCREF(Py_None);
+    return Py_None;
+}
+
+static PyObject * OutputWritelines(PyObject *self, PyObject *args)
+{
+    Py_ssize_t n;
+    Py_ssize_t i;
+    PyObject *list;
+    int error = ((OutputObject *)(self))->error;
+
+    if (!PyArg_ParseTuple(args, "O", &list))
+        return NULL;
+    Py_INCREF(list);
+
+    if (!PyList_Check(list)) {
+        PyErr_SetString(PyExc_TypeError, _("writelines() requires list of strings"));
+        Py_DECREF(list);
+        return NULL;
+    }
+
+    n = PyList_Size(list);
+
+    for (i = 0; i < n; ++i)
+    {
+        PyObject *line = PyList_GetItem(list, i);
+        char *str;
+        Py_ssize_t len;
+
+        if (!PyArg_Parse(line, "s#", &str, &len)) {
+            PyErr_SetString(PyExc_TypeError, _("writelines() requires list of strings"));
+            Py_DECREF(list);
+            return NULL;
+        }
+
+        Py_BEGIN_ALLOW_THREADS
+        Python_Lock_Vim();
+        writer((writefn)(error ? emsg : msg), (char_u *)str, len);
+        Python_Release_Vim();
+        Py_END_ALLOW_THREADS
+    }
+
+    Py_DECREF(list);
+    Py_INCREF(Py_None);
+    return Py_None;
+}
+
+/* Output buffer management
+ */
+
+static char_u *buffer = NULL;
+static Py_ssize_t buffer_len = 0;
+static Py_ssize_t buffer_size = 0;
+
+static writefn old_fn = NULL;
+
+static void buffer_ensure(Py_ssize_t n)
+{
+    Py_ssize_t new_size;
+    char_u *new_buffer;
+
+    if (n < buffer_size)
+        return;
+
+    new_size = buffer_size;
+    while (new_size < n)
+        new_size += 80;
+
+    if (new_size != buffer_size)
+    {
+        new_buffer = alloc((unsigned)new_size);
+        if (new_buffer == NULL)
+            return;
+
+        if (buffer)
+        {
+            memcpy(new_buffer, buffer, buffer_len);
+            vim_free(buffer);
+        }
+
+        buffer = new_buffer;
+        buffer_size = new_size;
+    }
+}
+
+static void PythonIO_Flush(void)
+{
+    if (old_fn && buffer_len)
+    {
+        buffer[buffer_len] = 0;
+        old_fn(buffer);
+    }
+
+    buffer_len = 0;
+}
+
+static void writer(writefn fn, char_u *str, Py_ssize_t n)
+{
+    char_u *ptr;
+
+    if (fn != old_fn && old_fn != NULL)
+        PythonIO_Flush();
+
+    old_fn = fn;
+
+    while (n > 0 && (ptr = memchr(str, '\n', n)) != NULL)
+    {
+        Py_ssize_t len = ptr - str;
+
+        buffer_ensure(buffer_len + len + 1);
+
+        memcpy(buffer + buffer_len, str, len);
+        buffer_len += len;
+        buffer[buffer_len] = 0;
+        fn(buffer);
+        str = ptr + 1;
+        n -= len + 1;
+        buffer_len = 0;
+    }
+
+    /* Put the remaining text into the buffer for later printing */
+    buffer_ensure(buffer_len + n + 1);
+    memcpy(buffer + buffer_len, str, n);
+    buffer_len += n;
+}
+
+/***************/
+
+static OutputObject Output =
+{
+    PyObject_HEAD_INIT(&OutputType)
+    0,
+    0
+};
+
+static OutputObject Error =
+{
+    PyObject_HEAD_INIT(&OutputType)
+    0,
+    1
+};
+
+static int PythonIO_Init(void)
+{
+    PyType_Ready(&OutputType);
+
+    PySys_SetObject("stdout", (PyObject *)(void *)&Output);
+    PySys_SetObject("stderr", (PyObject *)(void *)&Error);
+
+    if (PyErr_Occurred())
+    {
+        EMSG(_("E264: Python: Error initialising I/O objects"));
+        return -1;
+    }
+
+    return 0;
+}
+static void PythonIO_Fini(void)
+{
+    PySys_SetObject("stdout", NULL);
+    PySys_SetObject("stderr", NULL);
+}
+
+/******************************************************
+ * 3. Implementation of the Vim module for Python
+ */
+
+/* Vim module - Implementation functions
+ * -------------------------------------
+ */
+
+static PyObject *VimError;
+
+static PyObject *VimCommand(PyObject *, PyObject *);
+static PyObject *VimEval(PyObject *, PyObject *);
+
+/* Window type - Implementation functions
+ * --------------------------------------
+ */
+
+typedef struct
+{
+    PyObject_HEAD
+    win_T       *win;
+}
+WindowObject;
+
+#define INVALID_WINDOW_VALUE ((win_T *)(-1))
+
+#define WindowType_Check(obj) ((obj)->ob_base.ob_type == &WindowType)
+
+static PyObject *WindowNew(win_T *);
+
+static void WindowDestructor(PyObject *);
+static PyObject *WindowGetattro(PyObject *, PyObject *);
+static int WindowSetattro(PyObject *, PyObject *, PyObject *);
+static PyObject *WindowRepr(PyObject *);
+
+/* Buffer type - Implementation functions
+ * --------------------------------------
+ */
+
+typedef struct
+{
+    PyObject_HEAD
+    buf_T *buf;
+}
+BufferObject;
+
+#define INVALID_BUFFER_VALUE ((buf_T *)(-1))
+
+#define BufferType_Check(obj) ((obj)->ob_base.ob_type == &BufferType)
+
+static PyObject *BufferNew (buf_T *);
+
+static void BufferDestructor(PyObject *);
+
+static PyObject *BufferGetattro(PyObject *, PyObject*);
+static PyObject *BufferRepr(PyObject *);
+
+static Py_ssize_t BufferLength(PyObject *);
+static PyObject *BufferItem(PyObject *, Py_ssize_t);
+static Py_ssize_t BufferAsItem(PyObject *, Py_ssize_t, PyObject *);
+static PyObject* BufferSubscript(PyObject *self, PyObject* idx);
+
+static PyObject *BufferAppend(PyObject *, PyObject *);
+static PyObject *BufferMark(PyObject *, PyObject *);
+static PyObject *BufferRange(PyObject *, PyObject *);
+
+/* Line range type - Implementation functions
+ * --------------------------------------
+ */
+
+typedef struct
+{
+    PyObject_HEAD
+    BufferObject *buf;
+    Py_ssize_t start;
+    Py_ssize_t end;
+}
+RangeObject;
+
+#define RangeType_Check(obj) ((obj)->ob_base.ob_type == &RangeType)
+
+static PyObject *RangeNew(buf_T *, Py_ssize_t, Py_ssize_t);
+
+static void RangeDestructor(PyObject *);
+static PyObject *RangeGetattro(PyObject *, PyObject *);
+static PyObject *RangeRepr(PyObject *);
+static PyObject* RangeSubscript(PyObject *self, PyObject* idx);
+
+static Py_ssize_t RangeLength(PyObject *);
+static PyObject *RangeItem(PyObject *, Py_ssize_t);
+static Py_ssize_t RangeAsItem(PyObject *, Py_ssize_t, PyObject *);
+
+static PyObject *RangeAppend(PyObject *, PyObject *);
+
+/* Window list type - Implementation functions
+ * -------------------------------------------
+ */
+
+static Py_ssize_t WinListLength(PyObject *);
+static PyObject *WinListItem(PyObject *, Py_ssize_t);
+
+/* Buffer list type - Implementation functions
+ * -------------------------------------------
+ */
+
+static Py_ssize_t BufListLength(PyObject *);
+static PyObject *BufListItem(PyObject *, Py_ssize_t);
+
+/* Current objects type - Implementation functions
+ * -----------------------------------------------
+ */
+
+static PyObject *CurrentGetattro(PyObject *, PyObject *);
+static int CurrentSetattro(PyObject *, PyObject *, PyObject *);
+
+/* Vim module - Definitions
+ */
+
+static struct PyMethodDef VimMethods[] = {
+    /* name,         function,          calling,    documentation */
+    {"command",      VimCommand,        1,          "Execute a Vim ex-mode command" },
+    {"eval",         VimEval,           1,          "Evaluate an expression using Vim evaluator" },
+    { NULL,          NULL,              0,          NULL }
+};
+
+/* Vim module - Implementation
+ */
+/*ARGSUSED*/
+static PyObject * VimCommand(PyObject *self UNUSED, PyObject *args)
+{
+    char *cmd;
+    PyObject *result;
+
+    if (!PyArg_ParseTuple(args, "s", &cmd))
+        return NULL;
+
+    PyErr_Clear();
+
+    Py_BEGIN_ALLOW_THREADS
+    Python_Lock_Vim();
+
+    do_cmdline_cmd((char_u *)cmd);
+    update_screen(VALID);
+
+    Python_Release_Vim();
+    Py_END_ALLOW_THREADS
+
+    if (VimErrorCheck())
+        result = NULL;
+    else
+        result = Py_None;
+
+    Py_XINCREF(result);
+    return result;
+}
+
+#ifdef FEAT_EVAL
+/*
+ * Function to translate a typval_T into a PyObject; this will recursively
+ * translate lists/dictionaries into their Python equivalents.
+ *
+ * The depth parameter is to avoid infinite recursion, set it to 1 when
+ * you call VimToPython.
+ */
+static PyObject * VimToPython(typval_T *our_tv, int depth, PyObject *lookupDict)
+{
+    PyObject    *result;
+    PyObject    *newObj;
+    char        ptrBuf[NUMBUFLEN];
+
+    /* Avoid infinite recursion */
+    if (depth > 100)
+    {
+        Py_INCREF(Py_None);
+        result = Py_None;
+        return result;
+    }
+
+    /* Check if we run into a recursive loop.  The item must be in lookupDict
+     * then and we can use it again. */
+    if ((our_tv->v_type == VAR_LIST && our_tv->vval.v_list != NULL)
+            || (our_tv->v_type == VAR_DICT && our_tv->vval.v_dict != NULL))
+    {
+        sprintf(ptrBuf, PRINTF_DECIMAL_LONG_U,
+                our_tv->v_type == VAR_LIST ? (long_u)our_tv->vval.v_list
+                                           : (long_u)our_tv->vval.v_dict);
+        result = PyDict_GetItemString(lookupDict, ptrBuf);
+        if (result != NULL)
+        {
+            Py_INCREF(result);
+            return result;
+        }
+    }
+
+    if (our_tv->v_type == VAR_STRING)
+    {
+        result = Py_BuildValue("s", our_tv->vval.v_string);
+    }
+    else if (our_tv->v_type == VAR_NUMBER)
+    {
+        char buf[NUMBUFLEN];
+
+        /* For backwards compatibility numbers are stored as strings. */
+        sprintf(buf, "%ld", (long)our_tv->vval.v_number);
+        result = Py_BuildValue("s", buf);
+    }
+# ifdef FEAT_FLOAT
+    else if (our_tv->v_type == VAR_FLOAT)
+    {
+        char buf[NUMBUFLEN];
+
+        sprintf(buf, "%f", our_tv->vval.v_float);
+        result = Py_BuildValue("s", buf);
+    }
+# endif
+    else if (our_tv->v_type == VAR_LIST)
+    {
+        list_T          *list = our_tv->vval.v_list;
+        listitem_T      *curr;
+
+        result = PyList_New(0);
+
+        if (list != NULL)
+        {
+            PyDict_SetItemString(lookupDict, ptrBuf, result);
+
+            for (curr = list->lv_first; curr != NULL; curr = curr->li_next)
+            {
+                newObj = VimToPython(&curr->li_tv, depth + 1, lookupDict);
+                PyList_Append(result, newObj);
+                Py_DECREF(newObj);
+            }
+        }
+    }
+    else if (our_tv->v_type == VAR_DICT)
+    {
+        result = PyDict_New();
+
+        if (our_tv->vval.v_dict != NULL)
+        {
+            hashtab_T   *ht = &our_tv->vval.v_dict->dv_hashtab;
+            long_u      t = ht->ht_used;
+            hashitem_T  *hi;
+            dictitem_T  *di;
+
+            PyDict_SetItemString(lookupDict, ptrBuf, result);
+
+            for (hi = ht->ht_array; t > 0; ++hi)
+            {
+                if (!HASHITEM_EMPTY(hi))
+                {
+                    --t;
+
+                    di = dict_lookup(hi);
+                    newObj = VimToPython(&di->di_tv, depth + 1, lookupDict);
+                    PyDict_SetItemString(result, (char *)hi->hi_key, newObj);
+                    Py_DECREF(newObj);
+                }
+            }
+        }
+    }
+    else
+    {
+        Py_INCREF(Py_None);
+        result = Py_None;
+    }
+
+    return result;
+}
+#endif
+
+/*ARGSUSED*/
+static PyObject * VimEval(PyObject *self UNUSED, PyObject *args)
+{
+#ifdef FEAT_EVAL
+    char        *expr;
+    typval_T    *our_tv;
+    PyObject    *result;
+    PyObject    *lookup_dict;
+
+    if (!PyArg_ParseTuple(args, "s", &expr))
+        return NULL;
+
+    Py_BEGIN_ALLOW_THREADS
+    Python_Lock_Vim();
+    our_tv = eval_expr((char_u *)expr, NULL);
+
+    Python_Release_Vim();
+    Py_END_ALLOW_THREADS
+
+    if (our_tv == NULL)
+    {
+        PyErr_SetVim(_("invalid expression"));
+        return NULL;
+    }
+
+    /* Convert the Vim type into a Python type.  Create a dictionary that's
+     * used to check for recursive loops. */
+    lookup_dict = PyDict_New();
+    result = VimToPython(our_tv, 1, lookup_dict);
+    Py_DECREF(lookup_dict);
+
+
+    Py_BEGIN_ALLOW_THREADS
+    Python_Lock_Vim();
+    free_tv(our_tv);
+    Python_Release_Vim();
+    Py_END_ALLOW_THREADS
+
+    return result;
+#else
+    PyErr_SetVim(_("expressions disabled at compile time"));
+    return NULL;
+#endif
+}
+
+/* Common routines for buffers and line ranges
+ * -------------------------------------------
+ */
+
+static int CheckBuffer(BufferObject *this)
+{
+    if (this->buf == INVALID_BUFFER_VALUE)
+    {
+        PyErr_SetVim(_("attempt to refer to deleted buffer"));
+        return -1;
+    }
+
+    return 0;
+}
+
+static PyObject * RBItem(BufferObject *self, Py_ssize_t n, Py_ssize_t start, Py_ssize_t end)
+{
+    if (CheckBuffer(self))
+        return NULL;
+
+    if (n < 0 || n > end - start)
+    {
+        PyErr_SetString(PyExc_IndexError, _("line number out of range"));
+        return NULL;
+    }
+
+    return GetBufferLine(self->buf, n+start);
+}
+
+static Py_ssize_t RBAsItem(BufferObject *self, Py_ssize_t n, PyObject *val, Py_ssize_t start, Py_ssize_t end, Py_ssize_t *new_end)
+{
+    Py_ssize_t len_change;
+
+    if (CheckBuffer(self))
+        return -1;
+
+    if (n < 0 || n > end - start)
+    {
+        PyErr_SetString(PyExc_IndexError, _("line number out of range"));
+        return -1;
+    }
+
+    if (SetBufferLine(self->buf, n+start, val, &len_change) == FAIL)
+        return -1;
+
+    if (new_end)
+        *new_end = end + len_change;
+
+    return 0;
+}
+
+static PyObject * RBSlice(BufferObject *self, Py_ssize_t lo, Py_ssize_t hi, Py_ssize_t start, Py_ssize_t end)
+{
+    Py_ssize_t size;
+
+    if (CheckBuffer(self))
+        return NULL;
+
+    size = end - start + 1;
+
+    if (lo < 0)
+        lo = 0;
+    else if (lo > size)
+        lo = size;
+    if (hi < 0)
+        hi = 0;
+    if (hi < lo)
+        hi = lo;
+    else if (hi > size)
+        hi = size;
+
+    return GetBufferLineList(self->buf, lo+start, hi+start);
+}
+
+static PyObject * RBAppend(BufferObject *self, PyObject *args, Py_ssize_t start, Py_ssize_t end, Py_ssize_t *new_end)
+{
+    PyObject *lines;
+    Py_ssize_t len_change;
+    Py_ssize_t max;
+    Py_ssize_t n;
+
+    if (CheckBuffer(self))
+        return NULL;
+
+    max = n = end - start + 1;
+
+    if (!PyArg_ParseTuple(args, "O|n" , &lines, &n))
+        return NULL;
+
+    if (n < 0 || n > max)
+    {
+        PyErr_SetString(PyExc_ValueError, _("line number out of range"));
+        return NULL;
+    }
+
+    if (InsertBufferLines(self->buf, n + start - 1, lines, &len_change) == FAIL)
+        return NULL;
+
+    if (new_end)
+        *new_end = end + len_change;
+
+    Py_INCREF(Py_None);
+    return Py_None;
+}
+
+
+static struct PyMethodDef BufferMethods[] = {
+    /* name,        function,           calling,    documentation */
+    {"append",      BufferAppend,       1,          "Append data to Vim buffer" },
+    {"mark",        BufferMark,         1,          "Return (row,col) representing position of named mark" },
+    {"range",       BufferRange,        1,          "Return a range object which represents the part of the given buffer between line numbers s and e" },
+    { NULL,         NULL,               0,          NULL }
+};
+
+static PySequenceMethods BufferAsSeq = {
+    (lenfunc)           BufferLength,       /* sq_length,    len(x)   */
+    (binaryfunc)        0,                  /* sq_concat,    x+y      */
+    (ssizeargfunc)      0,                  /* sq_repeat,    x*n      */
+    (ssizeargfunc)      BufferItem,         /* sq_item,      x[i]     */
+    0,                                      /* was_sq_slice,     x[i:j]   */
+    (ssizeobjargproc)   BufferAsItem,       /* sq_ass_item,  x[i]=v   */
+    0,                                      /* sq_ass_slice, x[i:j]=v */
+    0,					    /* sq_contains */
+    0,					    /* sq_inplace_concat */
+    0,					    /* sq_inplace_repeat */
+};
+
+PyMappingMethods BufferAsMapping = {
+    /* mp_length        */ (lenfunc)BufferLength,
+    /* mp_subscript     */ (binaryfunc)BufferSubscript,
+    /* mp_ass_subscript */ (objobjargproc)0,
+};
+
+
+/* Buffer object - Definitions
+ */
+
+static PyTypeObject BufferType;
+
+static PyObject * BufferNew(buf_T *buf)
+{
+    /* We need to handle deletion of buffers underneath us.
+     * If we add a "b_python3_ref" field to the buf_T structure,
+     * then we can get at it in buf_freeall() in vim. We then
+     * need to create only ONE Python object per buffer - if
+     * we try to create a second, just INCREF the existing one
+     * and return it. The (single) Python object referring to
+     * the buffer is stored in "b_python3_ref".
+     * Question: what to do on a buf_freeall(). We'll probably
+     * have to either delete the Python object (DECREF it to
+     * zero - a bad idea, as it leaves dangling refs!) or
+     * set the buf_T * value to an invalid value (-1?), which
+     * means we need checks in all access functions... Bah.
+     */
+
+    BufferObject *self;
+
+    if (buf->b_python3_ref != NULL)
+    {
+        self = buf->b_python3_ref;
+        Py_INCREF(self);
+    }
+    else
+    {
+        self = PyObject_NEW(BufferObject, &BufferType);
+        buf->b_python3_ref = self;
+        if (self == NULL)
+            return NULL;
+        self->buf = buf;
+    }
+
+    return (PyObject *)(self);
+}
+
+static void BufferDestructor(PyObject *self)
+{
+    BufferObject *this = (BufferObject *)(self);
+
+    if (this->buf && this->buf != INVALID_BUFFER_VALUE)
+        this->buf->b_python3_ref = NULL;
+}
+
+static PyObject * BufferGetattro(PyObject *self, PyObject*nameobj)
+{
+    BufferObject *this = (BufferObject *)(self);
+
+    char *name = "";
+    if (PyUnicode_Check(nameobj))
+        name = _PyUnicode_AsString(nameobj);
+
+    if (CheckBuffer(this))
+        return NULL;
+
+    if (strcmp(name, "name") == 0)
+        return Py_BuildValue("s", this->buf->b_ffname);
+    else if (strcmp(name, "number") == 0)
+        return Py_BuildValue("n", this->buf->b_fnum);
+    else if (strcmp(name,"__members__") == 0)
+        return Py_BuildValue("[ss]", "name", "number");
+    else
+        return PyObject_GenericGetAttr(self, nameobj);
+}
+
+static PyObject * BufferRepr(PyObject *self)
+{
+    static char repr[100];
+    BufferObject *this = (BufferObject *)(self);
+
+    if (this->buf == INVALID_BUFFER_VALUE)
+    {
+        vim_snprintf(repr, 100, _("<buffer object (deleted) at %p>"), (self));
+        return PyUnicode_FromString(repr);
+    }
+    else
+    {
+        char *name = (char *)this->buf->b_fname;
+        Py_ssize_t len;
+
+        if (name == NULL)
+            name = "";
+        len = strlen(name);
+
+        if (len > 35)
+            name = name + (35 - len);
+
+        vim_snprintf(repr, 100, "<buffer %s%s>", len > 35 ? "..." : "", name);
+
+        return PyUnicode_FromString(repr);
+    }
+}
+
+/******************/
+
+static Py_ssize_t BufferLength(PyObject *self)
+{
+    if (CheckBuffer((BufferObject *)(self)))
+        return -1;
+
+    return (Py_ssize_t)(((BufferObject *)(self))->buf->b_ml.ml_line_count);
+}
+
+static PyObject * BufferItem(PyObject *self, Py_ssize_t n)
+{
+    return RBItem((BufferObject *)(self), n, 1,
+                  (Py_ssize_t)((BufferObject *)(self))->buf->b_ml.ml_line_count);
+}
+
+static Py_ssize_t BufferAsItem(PyObject *self, Py_ssize_t n, PyObject *val)
+{
+    return RBAsItem((BufferObject *)(self), n, val, 1,
+                     (Py_ssize_t)((BufferObject *)(self))->buf->b_ml.ml_line_count,
+                     NULL);
+}
+
+static PyObject * BufferSlice(PyObject *self, Py_ssize_t lo, Py_ssize_t hi)
+{
+    return RBSlice((BufferObject *)(self), lo, hi, 1,
+                   (Py_ssize_t)((BufferObject *)(self))->buf->b_ml.ml_line_count);
+}
+
+
+static PyObject* BufferSubscript(PyObject *self, PyObject* idx)
+{
+    if (PyLong_Check(idx)) {
+        long _idx = PyLong_AsLong(idx);
+        return BufferItem(self,_idx);
+    } else if (PySlice_Check(idx)) {
+        Py_ssize_t start, stop, step, slicelen;
+
+        if (PySlice_GetIndicesEx((PySliceObject *)idx,
+                                 (Py_ssize_t)((BufferObject *)(self))->buf->b_ml.ml_line_count+1,
+                                 &start, &stop,
+                                 &step, &slicelen) < 0) {
+                return NULL;
+        }
+        return BufferSlice(self,start,stop+1);
+    } else {
+        PyErr_SetString(PyExc_IndexError, "Index must be int or slice");
+        return NULL;
+    }
+}
+
+static PyObject * BufferAppend(PyObject *self, PyObject *args)
+{
+    return RBAppend((BufferObject *)(self), args, 1,
+                    (Py_ssize_t)((BufferObject *)(self))->buf->b_ml.ml_line_count,
+                    NULL);
+}
+
+static PyObject * BufferMark(PyObject *self, PyObject *args)
+{
+    pos_T       *posp;
+    char        *pmark;//test
+    char        mark;
+    buf_T       *curbuf_save;
+
+    if (CheckBuffer((BufferObject *)(self)))
+        return NULL;
+
+    if (!PyArg_ParseTuple(args, "s", &pmark))//test: "c"->"s"
+        return NULL;
+    mark = *pmark;//test
+
+    curbuf_save = curbuf;
+    curbuf = ((BufferObject *)(self))->buf;
+    posp = getmark(mark, FALSE);
+    curbuf = curbuf_save;
+
+    if (posp == NULL)
+    {
+        PyErr_SetVim(_("invalid mark name"));
+        return NULL;
+    }
+
+    /* Ckeck for keyboard interrupt */
+    if (VimErrorCheck())
+        return NULL;
+
+    if (posp->lnum <= 0)
+    {
+        /* Or raise an error? */
+        Py_INCREF(Py_None);
+        return Py_None;
+    }
+
+    return Py_BuildValue("(ll)", (long)(posp->lnum), (long)(posp->col));
+}
+
+static PyObject * BufferRange(PyObject *self, PyObject *args)
+{
+    Py_ssize_t start;
+    Py_ssize_t end;
+
+    if (CheckBuffer((BufferObject *)(self)))
+        return NULL;
+
+    if (!PyArg_ParseTuple(args, "nn", &start, &end))
+        return NULL;
+
+    return RangeNew(((BufferObject *)(self))->buf, start, end);
+}
+
+/* Line range object - Definitions
+ */
+
+static struct PyMethodDef RangeMethods[] = {
+    /* name,        function,           calling,    documentation */
+    {"append",      RangeAppend,        1,          "Append data to the Vim range" },
+    { NULL,         NULL,               0,          NULL }
+};
+
+static PySequenceMethods RangeAsSeq = {
+    (lenfunc)           RangeLength,     /* sq_length,    len(x)   */
+    (binaryfunc)        0,               /* RangeConcat, */          /* sq_concat,    x+y      */
+    (ssizeargfunc)      0,               /* RangeRepeat, */        /* sq_repeat,    x*n      */
+    (ssizeargfunc)      RangeItem,       /* sq_item,      x[i]     */
+    0,                                   /* was_sq_slice,     x[i:j]   */
+    (ssizeobjargproc)   RangeAsItem,     /* sq_as_item,  x[i]=v   */
+    0,                                      /* sq_ass_slice, x[i:j]=v */
+    0,					    /* sq_contains */
+    0,					    /* sq_inplace_concat */
+    0,					    /* sq_inplace_repeat */
+};
+
+PyMappingMethods RangeAsMapping = {
+    /* mp_length        */ (lenfunc)RangeLength,
+    /* mp_subscript     */ (binaryfunc)RangeSubscript,
+    /* mp_ass_subscript */ (objobjargproc)0,
+};
+
+static PyTypeObject RangeType;
+
+/* Line range object - Implementation
+ */
+
+static PyObject * RangeNew(buf_T *buf, Py_ssize_t start, Py_ssize_t end)
+{
+    BufferObject *bufr;
+    RangeObject *self;
+    self = PyObject_NEW(RangeObject, &RangeType);
+    if (self == NULL)
+        return NULL;
+
+    bufr = (BufferObject *)BufferNew(buf);
+    if (bufr == NULL)
+    {
+        Py_DECREF(self);
+        return NULL;
+    }
+    Py_INCREF(bufr);
+
+    self->buf = bufr;
+    self->start = start;
+    self->end = end;
+
+    return (PyObject *)(self);
+}
+
+static void RangeDestructor(PyObject *self)
+{
+    Py_DECREF(((RangeObject *)(self))->buf);
+}
+
+static PyObject * RangeGetattro(PyObject *self, PyObject *nameobj)
+{
+    char *name = "";
+    if (PyUnicode_Check(nameobj))
+        name = _PyUnicode_AsString(nameobj);
+
+    if (strcmp(name, "start") == 0)
+        return Py_BuildValue("n", ((RangeObject *)(self))->start - 1);
+    else if (strcmp(name, "end") == 0)
+        return Py_BuildValue("n", ((RangeObject *)(self))->end - 1);
+    else
+        return PyObject_GenericGetAttr(self, nameobj);
+}
+
+static PyObject * RangeRepr(PyObject *self)
+{
+    static char repr[100];
+    RangeObject *this = (RangeObject *)(self);
+
+    if (this->buf->buf == INVALID_BUFFER_VALUE)
+    {
+        vim_snprintf(repr, 100, "<range object (for deleted buffer) at %p>",
+                                                                      (self));
+        return PyUnicode_FromString(repr);
+    }
+    else
+    {
+        char *name = (char *)this->buf->buf->b_fname;
+        int len;
+
+        if (name == NULL)
+            name = "";
+        len = (int)strlen(name);
+
+        if (len > 45)
+            name = name + (45 - len);
+
+        vim_snprintf(repr, 100, "<range %s%s (%d:%d)>",
+                len > 45 ? "..." : "", name,
+                this->start, this->end);
+
+        return PyUnicode_FromString(repr);
+    }
+}
+
+/****************/
+
+static Py_ssize_t RangeLength(PyObject *self)
+{
+    /* HOW DO WE SIGNAL AN ERROR FROM THIS FUNCTION? */
+    if (CheckBuffer(((RangeObject *)(self))->buf))
+        return -1; /* ??? */
+
+    return (((RangeObject *)(self))->end - ((RangeObject *)(self))->start + 1);
+}
+
+static PyObject * RangeItem(PyObject *self, Py_ssize_t n)
+{
+    return RBItem(((RangeObject *)(self))->buf, n,
+                  ((RangeObject *)(self))->start,
+                  ((RangeObject *)(self))->end);
+}
+
+static Py_ssize_t RangeAsItem(PyObject *self, Py_ssize_t n, PyObject *val)
+{
+    return RBAsItem(((RangeObject *)(self))->buf, n, val,
+                     ((RangeObject *)(self))->start,
+                     ((RangeObject *)(self))->end,
+                     &((RangeObject *)(self))->end);
+}
+
+static PyObject * RangeSlice(PyObject *self, Py_ssize_t lo, Py_ssize_t hi)
+{
+    return RBSlice(((RangeObject *)(self))->buf, lo, hi,
+                   ((RangeObject *)(self))->start,
+                   ((RangeObject *)(self))->end);
+}
+
+static PyObject* RangeSubscript(PyObject *self, PyObject* idx)
+{
+    if (PyLong_Check(idx)) {
+        long _idx = PyLong_AsLong(idx);
+        return RangeItem(self,_idx);
+    } else if (PySlice_Check(idx)) {
+        Py_ssize_t start, stop, step, slicelen;
+
+        if (PySlice_GetIndicesEx((PySliceObject *)idx,
+                                 ((RangeObject *)(self))->end-((RangeObject *)(self))->start+1,
+                                 &start, &stop,
+                                 &step, &slicelen) < 0) {
+                return NULL;
+        }
+        return RangeSlice(self,start,stop+1);
+    } else {
+        PyErr_SetString(PyExc_IndexError, "Index must be int or slice");
+        return NULL;
+    }
+}
+
+static PyObject * RangeAppend(PyObject *self, PyObject *args)
+{
+    return RBAppend(((RangeObject *)(self))->buf, args,
+                    ((RangeObject *)(self))->start,
+                    ((RangeObject *)(self))->end,
+                    &((RangeObject *)(self))->end);
+}
+
+/* Buffer list object - Definitions
+ */
+
+typedef struct
+{
+    PyObject_HEAD
+}
+BufListObject;
+
+static PySequenceMethods BufListAsSeq = {
+    (lenfunc)           BufListLength,      /* sq_length,    len(x)   */
+    (binaryfunc)        0,                  /* sq_concat,    x+y      */
+    (ssizeargfunc)      0,                  /* sq_repeat,    x*n      */
+    (ssizeargfunc)      BufListItem,        /* sq_item,      x[i]     */
+    0,                                      /* was_sq_slice,     x[i:j]   */
+    (ssizeobjargproc)   0,                  /* sq_as_item,  x[i]=v   */
+    0,                                      /* sq_ass_slice, x[i:j]=v */
+    0,					    /* sq_contains */
+    0,					    /* sq_inplace_concat */
+    0,					    /* sq_inplace_repeat */
+};
+
+static PyTypeObject BufListType;
+
+/* Buffer list object - Implementation
+ */
+
+/*ARGSUSED*/
+static Py_ssize_t BufListLength(PyObject *self UNUSED)
+{
+    buf_T       *b = firstbuf;
+    Py_ssize_t  n = 0;
+
+    while (b)
+    {
+        ++n;
+        b = b->b_next;
+    }
+
+    return n;
+}
+
+/*ARGSUSED*/
+static PyObject * BufListItem(PyObject *self UNUSED, Py_ssize_t n)
+{
+    buf_T *b;
+
+    for (b = firstbuf; b; b = b->b_next, --n)
+    {
+        if (n == 0)
+            return BufferNew(b);
+    }
+
+    PyErr_SetString(PyExc_IndexError, _("no such buffer"));
+    return NULL;
+}
+
+/* Window object - Definitions
+ */
+
+static struct PyMethodDef WindowMethods[] = {
+    /* name,        function,           calling,    documentation */
+    { NULL,         NULL,               0,          NULL }
+};
+
+static PyTypeObject WindowType = {
+    PyVarObject_HEAD_INIT(NULL, 0)
+    "vim.window",             /* tp_name */
+    sizeof(WindowObject), /* tp_basicsize */
+    0,                         /* tp_itemsize */
+    WindowDestructor,                         /* tp_dealloc */
+    0,                         /* tp_print */
+    0,                         /* tp_getattr */
+    0,                         /* tp_setattr */
+    0,                         /* tp_reserved */
+    WindowRepr,                         /* tp_repr */
+    0,                         /* tp_as_number */
+    0,                         /* tp_as_sequence */
+    0,                         /* tp_as_mapping */
+    0,                         /* tp_hash  */
+    0,                         /* tp_call */
+    0,                         /* tp_str */
+    WindowGetattro,            /* tp_getattro */
+    WindowSetattro,            /* tp_setattro */
+    0,                         /* tp_as_Window */
+    Py_TPFLAGS_DEFAULT,        /* tp_flags */
+    "vim Window object",      /* tp_doc */
+    0,                         /*tp_traverse*/
+    0,                         /*tp_clear*/
+    0,                         /*tp_richcompare*/
+    0,                         /*tp_weaklistoffset*/
+    0,                         /*tp_iter*/
+    0,                         /*tp_iternext*/
+    WindowMethods,             /*tp_methods*/
+    0,                         /*tp_members*/
+    0,                         /*tp_getset*/
+    0,                         /*tp_base*/
+    0,                         /*tp_dict*/
+    0,                         /*tp_descr_get*/
+    0,                         /*tp_descr_set*/
+    0,                         /*tp_dictoffset*/
+    0,                         /*tp_init*/
+    call_PyType_GenericAlloc,       /*tp_alloc*/
+    call_PyType_GenericNew,         /*tp_new*/
+    call_PyObject_Free,             /*tp_free*/
+    0,                         /*tp_is_gc*/
+    0,				/*tp_bases*/
+    0,				/*tp_mro*/
+    0,				/*tp_cache*/
+    0,				/*tp_subclasses*/
+    0,				/*tp_weaklist*/
+    0,				/*tp_del*/
+    0,				/*tp_version_tag*/
+};
+
+/* Window object - Implementation
+ */
+
+static PyObject * WindowNew(win_T *win)
+{
+    /* We need to handle deletion of windows underneath us.
+     * If we add a "w_python3_ref" field to the win_T structure,
+     * then we can get at it in win_free() in vim. We then
+     * need to create only ONE Python object per window - if
+     * we try to create a second, just INCREF the existing one
+     * and return it. The (single) Python object referring to
+     * the window is stored in "w_python3_ref".
+     * On a win_free() we set the Python object's win_T* field
+     * to an invalid value. We trap all uses of a window
+     * object, and reject them if the win_T* field is invalid.
+     */
+
+    WindowObject *self;
+
+    if (win->w_python3_ref)
+    {
+        self = win->w_python3_ref;
+        Py_INCREF(self);
+    }
+    else
+    {
+        self = PyObject_NEW(WindowObject, &WindowType);
+        if (self == NULL)
+            return NULL;
+        self->win = win;
+        win->w_python3_ref = self;
+    }
+
+    return (PyObject *)(self);
+}
+
+static void WindowDestructor(PyObject *self)
+{
+    WindowObject *this = (WindowObject *)(self);
+
+    if (this->win && this->win != INVALID_WINDOW_VALUE)
+        this->win->w_python3_ref = NULL;
+}
+
+static int CheckWindow(WindowObject *this)
+{
+    if (this->win == INVALID_WINDOW_VALUE)
+    {
+        PyErr_SetVim(_("attempt to refer to deleted window"));
+        return -1;
+    }
+
+    return 0;
+}
+
+static PyObject * WindowGetattro(PyObject *self, PyObject *nameobj)
+{
+    WindowObject *this = (WindowObject *)(self);
+
+    char *name = "";
+    if (PyUnicode_Check(nameobj))
+        name = _PyUnicode_AsString(nameobj);
+
+
+    if (CheckWindow(this))
+        return NULL;
+
+    if (strcmp(name, "buffer") == 0)
+        return (PyObject *)BufferNew(this->win->w_buffer);
+    else if (strcmp(name, "cursor") == 0)
+    {
+        pos_T *pos = &this->win->w_cursor;
+
+        return Py_BuildValue("(ll)", (long)(pos->lnum), (long)(pos->col));
+    }
+    else if (strcmp(name, "height") == 0)
+        return Py_BuildValue("l", (long)(this->win->w_height));
+#ifdef FEAT_VERTSPLIT
+    else if (strcmp(name, "width") == 0)
+        return Py_BuildValue("l", (long)(W_WIDTH(this->win)));
+#endif
+    else if (strcmp(name,"__members__") == 0)
+        return Py_BuildValue("[sss]", "buffer", "cursor", "height");
+    else
+        return PyObject_GenericGetAttr(self, nameobj);
+}
+
+static int WindowSetattro(PyObject *self, PyObject *nameobj, PyObject *val)
+{
+    WindowObject *this = (WindowObject *)(self);
+
+    char *name = "";
+    if (PyUnicode_Check(nameobj))
+        name = _PyUnicode_AsString(nameobj);
+
+
+    if (CheckWindow(this))
+        return -1;
+
+    if (strcmp(name, "buffer") == 0)
+    {
+        PyErr_SetString(PyExc_TypeError, _("readonly attribute"));
+        return -1;
+    }
+    else if (strcmp(name, "cursor") == 0)
+    {
+        long lnum;
+        long col;
+
+        if (!PyArg_Parse(val, "(ll)", &lnum, &col))
+            return -1;
+
+        if (lnum <= 0 || lnum > this->win->w_buffer->b_ml.ml_line_count)
+        {
+            PyErr_SetVim(_("cursor position outside buffer"));
+            return -1;
+        }
+
+        /* Check for keyboard interrupts */
+        if (VimErrorCheck())
+            return -1;
+
+        /* NO CHECK ON COLUMN - SEEMS NOT TO MATTER */
+
+        this->win->w_cursor.lnum = lnum;
+        this->win->w_cursor.col = col;
+        update_screen(VALID);
+
+        return 0;
+    }
+    else if (strcmp(name, "height") == 0)
+    {
+        int     height;
+        win_T   *savewin;
+
+        if (!PyArg_Parse(val, "i", &height))
+            return -1;
+
+#ifdef FEAT_GUI
+        need_mouse_correct = TRUE;
+#endif
+        savewin = curwin;
+        curwin = this->win;
+        win_setheight(height);
+        curwin = savewin;
+
+        /* Check for keyboard interrupts */
+        if (VimErrorCheck())
+            return -1;
+
+        return 0;
+    }
+#ifdef FEAT_VERTSPLIT
+    else if (strcmp(name, "width") == 0)
+    {
+        int     width;
+        win_T   *savewin;
+
+        if (!PyArg_Parse(val, "i", &width))
+            return -1;
+
+#ifdef FEAT_GUI
+        need_mouse_correct = TRUE;
+#endif
+        savewin = curwin;
+        curwin = this->win;
+        win_setwidth(width);
+        curwin = savewin;
+
+        /* Check for keyboard interrupts */
+        if (VimErrorCheck())
+            return -1;
+
+        return 0;
+    }
+#endif
+    else
+    {
+        PyErr_SetString(PyExc_AttributeError, name);
+        return -1;
+    }
+}
+
+static PyObject * WindowRepr(PyObject *self)
+{
+    static char repr[100];
+    WindowObject *this = (WindowObject *)(self);
+
+    if (this->win == INVALID_WINDOW_VALUE)
+    {
+        vim_snprintf(repr, 100, _("<window object (deleted) at %p>"), (self));
+        return PyUnicode_FromString(repr);
+    }
+    else
+    {
+        int     i = 0;
+        win_T   *w;
+
+        for (w = firstwin; w != NULL && w != this->win; w = W_NEXT(w))
+            ++i;
+
+        if (w == NULL)
+            vim_snprintf(repr, 100, _("<window object (unknown) at %p>"),
+                                                                      (self));
+        else
+            vim_snprintf(repr, 100, _("<window %d>"), i);
+
+        return PyUnicode_FromString(repr);
+    }
+}
+
+/* Window list object - Definitions
+ */
+
+typedef struct
+{
+    PyObject_HEAD
+}
+WinListObject;
+
+static PySequenceMethods WinListAsSeq = {
+    (lenfunc)        WinListLength,         /* sq_length,    len(x)   */
+    (binaryfunc)     0,                     /* sq_concat,    x+y      */
+    (ssizeargfunc)   0,                     /* sq_repeat,    x*n      */
+    (ssizeargfunc)   WinListItem,           /* sq_item,      x[i]     */
+    0,                                      /* sq_slice,     x[i:j]   */
+    (ssizeobjargproc)0,                     /* sq_as_item,  x[i]=v   */
+    0,                                      /* sq_ass_slice, x[i:j]=v */
+    0,					    /* sq_contains */
+    0,					    /* sq_inplace_concat */
+    0,					    /* sq_inplace_repeat */
+};
+
+static PyTypeObject WinListType;
+
+/* Window list object - Implementation
+ */
+/*ARGSUSED*/
+static Py_ssize_t WinListLength(PyObject *self UNUSED)
+{
+    win_T       *w = firstwin;
+    Py_ssize_t  n = 0;
+
+    while (w != NULL)
+    {
+        ++n;
+        w = W_NEXT(w);
+    }
+
+    return n;
+}
+
+/*ARGSUSED*/
+static PyObject * WinListItem(PyObject *self UNUSED, Py_ssize_t n)
+{
+    win_T *w;
+
+    for (w = firstwin; w != NULL; w = W_NEXT(w), --n)
+        if (n == 0)
+            return WindowNew(w);
+
+    PyErr_SetString(PyExc_IndexError, _("no such window"));
+    return NULL;
+}
+
+/* Current items object - Definitions
+ */
+
+typedef struct
+{
+    PyObject_HEAD
+}
+CurrentObject;
+
+static PyTypeObject CurrentType;
+
+/* Current items object - Implementation
+ */
+/*ARGSUSED*/
+static PyObject * CurrentGetattro(PyObject *self UNUSED, PyObject *nameobj)
+{
+    char *name = "";
+    if (PyUnicode_Check(nameobj))
+        name = _PyUnicode_AsString(nameobj);
+
+    if (strcmp(name, "buffer") == 0)
+        return (PyObject *)BufferNew(curbuf);
+    else if (strcmp(name, "window") == 0)
+        return (PyObject *)WindowNew(curwin);
+    else if (strcmp(name, "line") == 0)
+        return GetBufferLine(curbuf, (Py_ssize_t)curwin->w_cursor.lnum);
+    else if (strcmp(name, "range") == 0)
+        return RangeNew(curbuf, RangeStart, RangeEnd);
+    else if (strcmp(name,"__members__") == 0)
+        return Py_BuildValue("[ssss]", "buffer", "window", "line", "range");
+    else
+    {
+        PyErr_SetString(PyExc_AttributeError, name);
+        return NULL;
+    }
+}
+
+/*ARGSUSED*/
+static int CurrentSetattro(PyObject *self UNUSED, PyObject *nameobj, PyObject *value)
+{
+    char *name = "";
+    if (PyUnicode_Check(nameobj))
+        name = _PyUnicode_AsString(nameobj);
+
+    if (strcmp(name, "line") == 0)
+    {
+        if (SetBufferLine(curbuf, (Py_ssize_t)curwin->w_cursor.lnum, value, NULL) == FAIL)
+            return -1;
+
+        return 0;
+    }
+    else
+    {
+        PyErr_SetString(PyExc_AttributeError, name);
+        return -1;
+    }
+}
+
+/* External interface
+ */
+
+    void
+python3_buffer_free(buf_T *buf)
+{
+    if (buf->b_python3_ref != NULL)
+    {
+        BufferObject *bp = buf->b_python3_ref;
+        bp->buf = INVALID_BUFFER_VALUE;
+        buf->b_python3_ref = NULL;
+    }
+}
+
+#if defined(FEAT_WINDOWS) || defined(PROTO)
+    void
+python3_window_free(win_T *win)
+{
+    if (win->w_python3_ref != NULL)
+    {
+        WindowObject *wp = win->w_python3_ref;
+        wp->win = INVALID_WINDOW_VALUE;
+        win->w_python3_ref = NULL;
+    }
+}
+#endif
+
+static BufListObject TheBufferList =
+{
+    PyObject_HEAD_INIT(&BufListType)
+};
+
+static WinListObject TheWindowList =
+{
+    PyObject_HEAD_INIT(&WinListType)
+};
+
+static CurrentObject TheCurrent =
+{
+    PyObject_HEAD_INIT(&CurrentType)
+};
+
+PyDoc_STRVAR(vim_module_doc,"vim python interface\n");
+
+static struct PyModuleDef vimmodule;
+
+PyMODINIT_FUNC Py3Init_vim(void)
+{
+    PyObject *mod;
+    /* The special value is removed from sys.path in Python3_Init(). */
+    static wchar_t *(argv[2]) = {L"/must>not&exist/foo", NULL};
+
+    PyType_Ready(&BufferType);
+    PyType_Ready(&RangeType);
+    PyType_Ready(&WindowType);
+    PyType_Ready(&BufListType);
+    PyType_Ready(&WinListType);
+    PyType_Ready(&CurrentType);
+
+    /* Set sys.argv[] to avoid a crash in warn(). */
+    PySys_SetArgv(1, argv);
+
+    mod = PyModule_Create(&vimmodule);
+
+    VimError = Py_BuildValue("s", "vim.error");
+
+    PyModule_AddObject(mod, "error", VimError);
+    Py_INCREF((PyObject *)(void *)&TheBufferList);
+    PyModule_AddObject(mod, "buffers", (PyObject *)(void *)&TheBufferList);
+    Py_INCREF((PyObject *)(void *)&TheCurrent);
+    PyModule_AddObject(mod, "current", (PyObject *)(void *)&TheCurrent);
+    Py_INCREF((PyObject *)(void *)&TheWindowList);
+    PyModule_AddObject(mod, "windows", (PyObject *)(void *)&TheWindowList);
+
+    if (PyErr_Occurred())
+        return NULL;
+
+    return mod;
+}
+
+/*************************************************************************
+ * 4. Utility functions for handling the interface between Vim and Python.
+ */
+
+
+/* Get a list of lines from the specified buffer. The line numbers
+ * are in Vim format (1-based). The range is from lo up to, but not
+ * including, hi. The list is returned as a Python list of string objects.
+ */
+static PyObject * GetBufferLineList(buf_T *buf, Py_ssize_t lo, Py_ssize_t hi)
+{
+    Py_ssize_t i;
+    Py_ssize_t n = hi - lo;
+    PyObject *list = PyList_New(n);
+
+    if (list == NULL)
+        return NULL;
+
+    for (i = 0; i < n; ++i)
+    {
+        PyObject *str = LineToString((char *)ml_get_buf(buf, (linenr_T)(lo+i), FALSE));
+
+        /* Error check - was the Python string creation OK? */
+        if (str == NULL)
+        {
+            Py_DECREF(list);
+            return NULL;
+        }
+
+        /* Set the list item */
+        if (PyList_SetItem(list, i, str))
+        {
+            Py_DECREF(str);
+            Py_DECREF(list);
+            return NULL;
+        }
+    }
+
+    /* The ownership of the Python list is passed to the caller (ie,
+     * the caller should Py_DECREF() the object when it is finished
+     * with it).
+     */
+
+    return list;
+}
+
+/* Get a line from the specified buffer. The line number is
+ * in Vim format (1-based). The line is returned as a Python
+ * string object.
+ */
+static PyObject * GetBufferLine(buf_T *buf, Py_ssize_t n)
+{
+    return LineToString((char *)ml_get_buf(buf, (linenr_T)n, FALSE));
+}
+
+/*
+ * Check if deleting lines made the cursor position invalid.
+ * Changed the lines from "lo" to "hi" and added "extra" lines (negative if
+ * deleted).
+ */
+static void py_fix_cursor(linenr_T lo, linenr_T hi, linenr_T extra)
+{
+    if (curwin->w_cursor.lnum >= lo)
+    {
+        /* Adjust the cursor position if it's in/after the changed
+         * lines. */
+        if (curwin->w_cursor.lnum >= hi)
+        {
+            curwin->w_cursor.lnum += extra;
+            check_cursor_col();
+        }
+        else if (extra < 0)
+        {
+            curwin->w_cursor.lnum = lo;
+            check_cursor();
+        }
+        else
+            check_cursor_col();
+        changed_cline_bef_curs();
+    }
+    invalidate_botline();
+}
+
+/* Replace a line in the specified buffer. The line number is
+ * in Vim format (1-based). The replacement line is given as
+ * a Python string object. The object is checked for validity
+ * and correct format. Errors are returned as a value of FAIL.
+ * The return value is OK on success.
+ * If OK is returned and len_change is not NULL, *len_change
+ * is set to the change in the buffer length.
+ */
+static int SetBufferLine(buf_T *buf, Py_ssize_t n, PyObject *line, Py_ssize_t *len_change)
+{
+    /* First of all, we check the thpe of the supplied Python object.
+     * There are three cases:
+     *    1. NULL, or None - this is a deletion.
+     *    2. A string      - this is a replacement.
+     *    3. Anything else - this is an error.
+     */
+    if (line == Py_None || line == NULL)
+    {
+        buf_T *savebuf = curbuf;
+
+        PyErr_Clear();
+        curbuf = buf;
+
+        if (u_savedel((linenr_T)n, 1L) == FAIL)
+            PyErr_SetVim(_("cannot save undo information"));
+        else if (ml_delete((linenr_T)n, FALSE) == FAIL)
+            PyErr_SetVim(_("cannot delete line"));
+        else
+        {
+            deleted_lines_mark((linenr_T)n, 1L);
+            if (buf == curwin->w_buffer)
+                py_fix_cursor((linenr_T)n, (linenr_T)n + 1, (linenr_T)-1);
+        }
+
+        curbuf = savebuf;
+
+        if (PyErr_Occurred() || VimErrorCheck())
+            return FAIL;
+
+        if (len_change)
+            *len_change = -1;
+
+        return OK;
+    }
+    else if (PyUnicode_Check(line))
+    {
+        char *save = StringToLine(line);
+        buf_T *savebuf = curbuf;
+
+        if (save == NULL)
+            return FAIL;
+
+        /* We do not need to free "save" if ml_replace() consumes it. */
+        PyErr_Clear();
+        curbuf = buf;
+
+        if (u_savesub((linenr_T)n) == FAIL)
+        {
+            PyErr_SetVim(_("cannot save undo information"));
+            vim_free(save);
+        }
+        else if (ml_replace((linenr_T)n, (char_u *)save, FALSE) == FAIL)
+        {
+            PyErr_SetVim(_("cannot replace line"));
+            vim_free(save);
+        }
+        else
+            changed_bytes((linenr_T)n, 0);
+
+        curbuf = savebuf;
+
+        /* Check that the cursor is not beyond the end of the line now. */
+        if (buf == curwin->w_buffer)
+            check_cursor_col();
+
+        if (PyErr_Occurred() || VimErrorCheck())
+            return FAIL;
+
+        if (len_change)
+            *len_change = 0;
+
+        return OK;
+    }
+    else
+    {
+        PyErr_BadArgument();
+        return FAIL;
+    }
+}
+
+/* Insert a number of lines into the specified buffer after the specifed line.
+ * The line number is in Vim format (1-based). The lines to be inserted are
+ * given as a Python list of string objects or as a single string. The lines
+ * to be added are checked for validity and correct format. Errors are
+ * returned as a value of FAIL.  The return value is OK on success.
+ * If OK is returned and len_change is not NULL, *len_change
+ * is set to the change in the buffer length.
+ */
+static int InsertBufferLines(buf_T *buf, Py_ssize_t n, PyObject *lines, Py_ssize_t *len_change)
+{
+    /* First of all, we check the type of the supplied Python object.
+     * It must be a string or a list, or the call is in error.
+     */
+    if (PyUnicode_Check(lines))
+    {
+        char    *str = StringToLine(lines);
+        buf_T   *savebuf;
+
+        if (str == NULL)
+            return FAIL;
+
+        savebuf = curbuf;
+
+        PyErr_Clear();
+        curbuf = buf;
+
+        if (u_save((linenr_T)n, (linenr_T)(n+1)) == FAIL)
+            PyErr_SetVim(_("cannot save undo information"));
+        else if (ml_append((linenr_T)n, (char_u *)str, 0, FALSE) == FAIL)
+            PyErr_SetVim(_("cannot insert line"));
+        else
+            appended_lines_mark((linenr_T)n, 1L);
+
+        vim_free(str);
+        curbuf = savebuf;
+        update_screen(VALID);
+
+        if (PyErr_Occurred() || VimErrorCheck())
+            return FAIL;
+
+        if (len_change)
+            *len_change = 1;
+
+        return OK;
+    }
+    else if (PyList_Check(lines))
+    {
+        Py_ssize_t      i;
+        Py_ssize_t      size = PyList_Size(lines);
+        char    **array;
+        buf_T   *savebuf;
+
+        array = (char **)alloc((unsigned)(size * sizeof(char *)));
+        if (array == NULL)
+        {
+            PyErr_NoMemory();
+            return FAIL;
+        }
+
+        for (i = 0; i < size; ++i)
+        {
+            PyObject *line = PyList_GetItem(lines, i);
+            array[i] = StringToLine(line);
+
+            if (array[i] == NULL)
+            {
+                while (i)
+                    vim_free(array[--i]);
+                vim_free(array);
+                return FAIL;
+            }
+        }
+
+        savebuf = curbuf;
+
+        PyErr_Clear();
+        curbuf = buf;
+
+        if (u_save((linenr_T)n, (linenr_T)(n + 1)) == FAIL)
+            PyErr_SetVim(_("cannot save undo information"));
+        else
+        {
+            for (i = 0; i < size; ++i)
+            {
+                if (ml_append((linenr_T)(n + i),
+                                        (char_u *)array[i], 0, FALSE) == FAIL)
+                {
+                    PyErr_SetVim(_("cannot insert line"));
+
+                    /* Free the rest of the lines */
+                    while (i < size)
+                        vim_free(array[i++]);
+
+                    break;
+                }
+                vim_free(array[i]);
+            }
+            if (i > 0)
+                appended_lines_mark((linenr_T)n, (long)i);
+        }
+
+        /* Free the array of lines. All of its contents have now
+         * been freed.
+         */
+        vim_free(array);
+
+        curbuf = savebuf;
+        update_screen(VALID);
+
+        if (PyErr_Occurred() || VimErrorCheck())
+            return FAIL;
+
+        if (len_change)
+            *len_change = size;
+
+        return OK;
+    }
+    else
+    {
+        PyErr_BadArgument();
+        return FAIL;
+    }
+}
+
+/* Convert a Vim line into a Python string.
+ * All internal newlines are replaced by null characters.
+ *
+ * On errors, the Python exception data is set, and NULL is returned.
+ */
+static PyObject * LineToString(const char *str)
+{
+    PyObject *result;
+    Py_ssize_t len = strlen(str);
+    char *tmp,*p;
+
+    tmp = (char *)alloc((unsigned)(len+1));
+    p = tmp;
+    if (p == NULL)
+    {
+        PyErr_NoMemory();
+        return NULL;
+    }
+
+    while (*str)
+    {
+        if (*str == '\n')
+            *p = '\0';
+        else
+            *p = *str;
+
+        ++p;
+        ++str;
+    }
+    *p = '\0';
+
+    result = PyUnicode_FromStringAndSize(tmp, len);
+
+    vim_free(tmp);
+    return result;
+}
+
+/* Convert a Python string into a Vim line.
+ *
+ * The result is in allocated memory. All internal nulls are replaced by
+ * newline characters. It is an error for the string to contain newline
+ * characters.
+ *
+ * On errors, the Python exception data is set, and NULL is returned.
+ */
+static char * StringToLine(PyObject *obj)
+{
+    const char *str;
+    char *save;
+    Py_ssize_t len;
+    Py_ssize_t i;
+    char *p;
+
+    if (obj == NULL || !PyUnicode_Check(obj))
+    {
+        PyErr_BadArgument();
+        return NULL;
+    }
+
+    str = _PyUnicode_AsString(obj);
+    len = PyUnicode_GET_SIZE(obj);
+
+    /*
+     * Error checking: String must not contain newlines, as we
+     * are replacing a single line, and we must replace it with
+     * a single line.
+     * A trailing newline is removed, so that append(f.readlines()) works.
+     */
+    p = memchr(str, '\n', len);
+    if (p != NULL)
+    {
+        if (p == str + len - 1)
+            --len;
+        else
+        {
+            PyErr_SetVim(_("string cannot contain newlines"));
+            return NULL;
+        }
+    }
+
+    /* Create a copy of the string, with internal nulls replaced by
+     * newline characters, as is the vim convention.
+     */
+    save = (char *)alloc((unsigned)(len+1));
+    if (save == NULL)
+    {
+        PyErr_NoMemory();
+        return NULL;
+    }
+
+    for (i = 0; i < len; ++i)
+    {
+        if (str[i] == '\0')
+            save[i] = '\n';
+        else
+            save[i] = str[i];
+    }
+
+    save[i] = '\0';
+
+    return save;
+}
+
+/* Check to see whether a Vim error has been reported, or a keyboard
+ * interrupt has been detected.
+ */
+static int VimErrorCheck(void)
+{
+    if (got_int)
+    {
+        PyErr_SetNone(PyExc_KeyboardInterrupt);
+        return 1;
+    }
+    else if (did_emsg && !PyErr_Occurred())
+    {
+        PyErr_SetNone(VimError);
+        return 1;
+    }
+
+    return 0;
+}
+
+
+static void init_structs(void)
+{
+    vim_memset(&OutputType, 0, sizeof(OutputType));
+    OutputType.tp_name = "vim.message";
+    OutputType.tp_basicsize = sizeof(OutputObject);
+    OutputType.tp_getattro = OutputGetattro;
+    OutputType.tp_setattro = OutputSetattro;
+    OutputType.tp_flags = Py_TPFLAGS_DEFAULT;
+    OutputType.tp_doc = "vim message object";
+    OutputType.tp_methods = OutputMethods;
+    OutputType.tp_alloc = call_PyType_GenericAlloc;
+    OutputType.tp_new = call_PyType_GenericNew;
+    OutputType.tp_free = call_PyObject_Free;
+
+    vim_memset(&BufferType, 0, sizeof(BufferType));
+    BufferType.tp_name = "vim.buffer";
+    BufferType.tp_basicsize = sizeof(BufferType);
+    BufferType.tp_dealloc = BufferDestructor;
+    BufferType.tp_repr = BufferRepr;
+    BufferType.tp_as_sequence = &BufferAsSeq;
+    BufferType.tp_as_mapping = &BufferAsMapping;
+    BufferType.tp_getattro = BufferGetattro;
+    BufferType.tp_flags = Py_TPFLAGS_DEFAULT;
+    BufferType.tp_doc = "vim buffer object";
+    BufferType.tp_methods = BufferMethods;
+    BufferType.tp_alloc = call_PyType_GenericAlloc;
+    BufferType.tp_new = call_PyType_GenericNew;
+    BufferType.tp_free = call_PyObject_Free;
+
+    vim_memset(&BufListType, 0, sizeof(BufListType));
+    BufListType.tp_name = "vim.bufferlist";
+    BufListType.tp_basicsize = sizeof(BufListObject);
+    BufListType.tp_as_sequence = &BufListAsSeq;
+    BufListType.tp_flags = Py_TPFLAGS_DEFAULT;
+    BufferType.tp_doc = "vim buffer list";
+
+    vim_memset(&WinListType, 0, sizeof(WinListType));
+    WinListType.tp_name = "vim.windowlist";
+    WinListType.tp_basicsize = sizeof(WinListType);
+    WinListType.tp_as_sequence = &WinListAsSeq;
+    WinListType.tp_flags = Py_TPFLAGS_DEFAULT;
+    WinListType.tp_doc = "vim window list";
+
+    vim_memset(&RangeType, 0, sizeof(RangeType));
+    RangeType.tp_name = "vim.range";
+    RangeType.tp_basicsize = sizeof(RangeObject);
+    RangeType.tp_dealloc = RangeDestructor;
+    RangeType.tp_repr = RangeRepr;
+    RangeType.tp_as_sequence = &RangeAsSeq;
+    RangeType.tp_as_mapping = &RangeAsMapping;
+    RangeType.tp_getattro = RangeGetattro;
+    RangeType.tp_flags = Py_TPFLAGS_DEFAULT;
+    RangeType.tp_doc = "vim Range object";
+    RangeType.tp_methods = RangeMethods;
+    RangeType.tp_alloc = call_PyType_GenericAlloc;
+    RangeType.tp_new = call_PyType_GenericNew;
+    RangeType.tp_free = call_PyObject_Free;
+
+    vim_memset(&CurrentType, 0, sizeof(CurrentType));
+    CurrentType.tp_name = "vim.currentdata";
+    CurrentType.tp_basicsize = sizeof(CurrentObject);
+    CurrentType.tp_getattro = CurrentGetattro;
+    CurrentType.tp_setattro = CurrentSetattro;
+    CurrentType.tp_flags = Py_TPFLAGS_DEFAULT;
+    CurrentType.tp_doc = "vim current object";
+
+    vim_memset(&vimmodule, 0, sizeof(vimmodule));
+    vimmodule.m_name = "vim";
+    vimmodule.m_doc = vim_module_doc;
+    vimmodule.m_size = -1;
+    vimmodule.m_methods = VimMethods;
+}