pypa/pip — pull request #1529 by dongweiming (2014-02-04 02:20:53+00:00)
Title: Bugfix: when not find a version that satisfies the requirement. show all versions but duplicate

When i install ipython:

```
sudo pip install ipython==1.0.dev
Downloading/unpacking ipython==1.0.dev
Could not find a version that satisfies the requirement ipython==1.0.dev (from versions: 0.10.1, 0.10.1, 0.10.2, 0.10.2, 0.10, 0.11, 0.11, 0.12.1, 0.12.1, 0.12, 0.12, 0.13.1, 0.13.1, 0.13.2, 0.13.2, 0.13, 0.13, 1.0.0, 1.0.0, 1.1.0, 1.1.0)
Some externally hosted files were ignored (use --allow-external to allow).
Cleaning up...
No distributions matching the version for ipython==1.0.dev
Storing debug log for failure in /home/dongwm/.pip/pip.log
```

You can see `0.10.2` display twice, and more duplicate.

The reason is ipython put a zip and tar.gz but is a version so you need to remove duplicate