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#language en
== Updating Python ==

If you want to change the Python running your MoinMoin installation there are some issues to keep in mind:

=== Location of the MoinMoin directory ===

The default installation process (`setup.py`) installed the MoinMoin files into the site-packages directory of the current Python installation (for example `/usr/lib/python2.2/site-packages`). If you move to another Python interpreter you must reinstall the MoinMoin files into the new `lib/pythonX.X/site-packeges` directory. If you installed the MoinMoin files elsewhere and adjusted `sys.path` this is not a problem.

=== The precompiled Python files (.pyc) ===

Python does not grant that .pyc files are compatible between Python versions. If you change the Python interpreter you should recompile the Python scripts. You may use 

{{{
python -c "import compileall; compileall.compile_dir('/path/to/MoinMoin')"
}}}

for this. If you reinstall MoinMoin for the new interpreter the step is not needed/done by setup.py.

=== Empty Page Cache ===

The page cache uses Python byte code for faster page rendering. To avoid compatibility problems you should empty the cache by hand by deleting all files in `data/pages/*/cache/` and `underlay/pages/*/cache/`.