updated for version 7.3.579
Problem:    Can't compile with Python 2.5.
Solution:   Use PyCObject when Capsules are not available.
diff --git a/src/if_python3.c b/src/if_python3.c
index c4e122c..a62971e 100644
--- a/src/if_python3.c
+++ b/src/if_python3.c
@@ -75,6 +75,9 @@
 # define CODEC_ERROR_HANDLER NULL
 #endif
 
+/* Python 3 does not support CObjects, always use Capsules */
+#define PY_USE_CAPSULE
+
 #define PyInt Py_ssize_t
 #define PyString_Check(obj) PyUnicode_Check(obj)
 #define PyString_AsBytes(obj) PyUnicode_AsEncodedString(obj, (char *)ENC_OPT, CODEC_ERROR_HANDLER)