diff --git a/runtime/doc/if_pyth.txt b/runtime/doc/if_pyth.txt
index b8073cf..d37bd49 100644
--- a/runtime/doc/if_pyth.txt
+++ b/runtime/doc/if_pyth.txt
@@ -176,6 +176,10 @@
 	|python-bindeval-objects|. These python objects let you modify (|List| 
 	or |Dictionary|) or call (|Funcref|) vim objects.
 
+vim.strwidth(str)					*python-strwidth*
+	Like |strwidth()|: returns number of display cells str occupies, tab 
+	is counted as one cell.
+
 Error object of the "vim" module
 
 vim.error						*python-error*
@@ -329,6 +333,8 @@
 			|BufFilePost| autocommands are launched.
 	b.number	Buffer number. Can be used as |python-buffers| key.
 			Read-only.
+	b.valid		True or False. Buffer object becames invalid when 
+			corresponding buffer is wiped out.
 
 The buffer object methods are:
 	b.append(str)	Append a line to the buffer
@@ -433,6 +439,8 @@
 	row, col (read-only)	On-screen window position in display cells.
 				First position is zero.
 	tabpage (read-only)	Window tab page.
+	valid (read-write)	True or False. Window object becames invalid 
+				when corresponding window is closed.
 
 The height attribute is writable only if the screen is split horizontally.
 The width attribute is writable only if the screen is split vertically.
@@ -456,6 +464,8 @@
 	windows		Like |python-windows|, but for current tab page.
 	vars		The tab page |t:| variables.
 	window		Current tabpage window.
+	valid		True or False. Tab page object becames invalid when 
+			corresponding tab page is closed.
 
 TabPage object type is available using "TabPage" attribute of vim module.