Create setup.py
Update models.py

Might as well call uuid4 directly than have a pointless method that does it.
By placing FILE_FORMATS outside the model you have it accessible to any future code you write (DRY)
For urls, URLField is better than CharField
Merge pull request #1 from draringi/patch-1

Create setup.py
Merge pull request #2 from draringi/patch-2

Update models.py
setup.py was misplaced. It is now in the correct place