cliff is being developed under Python 2.7 and tested with Python 3.2.
cliff depends on distribute, the updated replacement for setuptools. If you have an older version of setuptools installed, you may have trouble installing cliff until you upgrade or set up a virtualenv using distribute instead (by using --use-distribute).
cliff should be installed into the same site-packages area where the application and extensions are installed (either a virtualenv or the global site-packages). You may need administrative privileges to do that. The easiest way to install it is using pip:
$ pip install cliff
$ sudo pip install cliff