How to fix ImportError: No module named packages.urllib3?

Question

I\'m running Python 2.7.6 on an Ubuntu machine. When I run twill-sh (Twill is a browser used for testing websites) in my Terminal, I\'m getting the following:

Answer 1

If you already have 'requests' installed from a default build, you may have to

sudo pip install --upgrade requests

Credit to @bkzland from comment on previous answer:

I followed these steps having the same error, I needed to use sudo pip install --upgrade each time to make it work. – bkzland Dec 17 '15 at 12:57

---now, how do I make this a dependency in my setup.py?