如果使用setup.py进行安装，只需通过相应版本的Python运行它，例如:

If you're installing using setup.py, just run it via the appropriate version of Python, e.g.:

python2.6 setup.py install

如果您使用的是easy_install，则对应的Python版本应有一个名为easy_install-N.N的版本，例如

If you're using easy_install there should be a version for the corresponding Python version called easy_install-N.N, e.g.

easy_install-2.6 some_module

如果您正在从事需要不同版本Python的不同项目，请考虑使用 virtualenv (和 virtualenvwrapper )-它允许您启动并使用具有各自版本的多个环境Python和一组库.用法示例如下:

If you're working on different projects that require different versions of Python, consider using virtualenv (and virtualenvwrapper) - it allows you to fire up and use multiple environments each with its own version of Python and set of libraries. Example usage would be something like:

$ python -V
Python 2.5.4
$ mkvirtualenv --python=python2.6 foo
foo $ python -V
Python 2.6.1
foo $ pip install some_mod # installs module in foo's library, rather
                           # than site wide
foo $ deactivate # leave the virtual env
$ python -m some_mod
/path/to/python: No module named some_mod

要稍后返回foo环境，请使用workon:

To go back to the foo environment later, use workon:

$ workon foo
foo $ python -m some_mod # no error, apns available within the env
foo $ 

因此，您可以使用virtualenv为已安装的每个Python版本维护单独的环境.在这些环境中，pip和easy_install会做正确的事.

So you can use virtualenv to maintain separate environments for each version of Python you have installed. Within those environments, pip and easy_install just do the right thing.