sympy/sympy — pull request #1446 by scolobb (2012-07-28 21:20:23+00:00)
Title: Add sorted_args and fix the sort keys for some unordered collections.

This pull request adds `sorted_args` to `Basic`, attempts to make all the code which needs sorted `args` use this new property. Furthermore, this pull request makes `FiniteSet` and `Dict` produce hash-independent sort keys.