How to uninstall all python versions and use the default system version of OS X 10.10?

Question

I'm looking for a way to cleanly uninstall all versions of python on OS X 10.10 except the default version that followed with the Mac. How do I proceed?

Currently I've some weird behaviour. When typing which -a python I get the following output:

/Users/harisfawad/anaconda/bin/python
/Library/Frameworks/Python.framework/Versions/2.7/bin/python
/usr/local/bin/python
/usr/bin/python

Why doesn't the default version of python in /System/Library/.../ show up here? I can locate that version in Finder, so I know that it isn't deleted.

Also, echo $PYTHONPATH returns an empty line.

Can I just go ahead and delete all these folders and expect the default version to run correctly?

I've read a similar inquiry here http://bugs.python.org/issue7107 but I'm not sure if this is still applicable to python versions 2.7/3.4.

This is also a similar question How to uninstall Python 2.7 on a Mac OS X 10.6.4? But again, I don't want to be careless and do the uninstalling before making sure that the system provided version works.

UPDATE: When running brew doctor I get this Warning: "config" scripts exist outside your system or Homebrew directories. And it goes on listing the "config" files in /.../anaconda/bin and in /Library/.../bin.

UPDATE2: I've successfully gone back to the default version of python that was included in OS X. All the above versions of python where moved to trash, except /usr/bin/python. Thanks, @rhashimoto and @PadraicCunningham!

Answer 1

The file /usr/bin/python (and /usr/bin/pythonw, which is a hard link to the same file) is actually a launcher program that invokes the default version of Python from /System/Library/Frameworks/Python.framework/Versions. You can select the version (2.6 and 2.7 in Yosemite) the launcher invokes using either the defaults command or the VERSIONER_PYTHON_VERSION environment variable.

If you want to run a specific version manually, you can invoke /usr/bin/python2.6 or /usr/bin/python2.7, which are symbolic links into /System/Library/Frameworks/Python.framework/Versions.

You should be fine removing all other Python implementations you list from your path, including /Library/Frameworks/Python.framework/Versions/2.7/bin/python (not sure how you got that one). It would still be wise to move them somewhere (e.g. your trash folder) to test your change before deleting them permanently.