[throwaway9101]

Codechef appears to use Python 3.1.2 for "Python3", which is pretty old (March 21st, 2010) and predates some significant performance improvements in Python3[0].

[0]: E.g., 3.3 adds a more efficient encoding for ASCII-subset unicode strings: http://docs.python.org/3/whatsnew/3.3.html#performance-and-r...