sympy/sympy — pull request #1106 by vinoo (2012-03-06 12:20:48+00:00)
Title: Issue 2328 Solved

http://code.google.com/p/sympy/issues/detail?id=2328&q=label%3AEasyToFix&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20Stars

The solution to the above issue. Issue number 2328.
I'm checking the hints dictionary to see if it contains valid keys, if it does not contain valid keys i'm raising a Type Error.