Full_Name: Guido van Rossum Version: 1.5.2 OS: Solaris 2.7 Submission from: eric.cnri.reston.va.us (132.151.1.38) When PyArg_ParseTuple() needs an int (for an 'i' format char) but finds something else, it says TypeError: illegal argument type for built-in operation instead of the nice friendly error it usually gives.