expose PYTHON_API_VERSION macro as sys.api_version. Closes patch # 601456.
diff --git a/Doc/lib/libsys.tex b/Doc/lib/libsys.tex
index 4aa2d4a..eec02e0 100644
--- a/Doc/lib/libsys.tex
+++ b/Doc/lib/libsys.tex
@@ -459,6 +459,12 @@
\end{verbatim}
\end{datadesc}
+\begin{datadesc}{api_version}
+ The C API version for this interpreter. Programmers may find this useful
+ when debugging version conflicts between Python and extension
+ modules. \versionadded{2.3}
+\end{datadesc}
+
\begin{datadesc}{version_info}
A tuple containing the five components of the version number:
\var{major}, \var{minor}, \var{micro}, \var{releaselevel}, and