PyArg_ParseTupleAndKeywords: return false on internal error, not -1 (I introduced this bug just a little while ago, when *adding* internal error checks). vgetargskeywords: Rewrote the section that crawls over the format string. + Added block comment so it won't take the next person 15 minutes to reverse-engineer what it's doing. + Lined up the "else" clauses. + Rearranged the ifs in decreasing order of likelihood (for speed).