AllPairs is an open source test combinations generator. It allows one to
create a set of tests using "pairwise combinations" method, reducing a
number of combinations of variables into a lesser set that covers most
situations. Features:

- Produces good enough dataset.
- Pythonic, iterator-style enumeration interface.
- Allows to filter out "invalid" combinations during search for the next
  combination.
- Goes beyond pairs! If/when required can generate n-wise combinations.