Without qualification, Guido van Rossum (author of Python). Note that Guido answers to English /gweeŽdo/ but in Dutch it's /khweeŽdo/. Mythically, Guido's most important attribute besides Python itself is Guido's time machine, a device he is reputed to possess because of the unnerving frequency with which user requests for new features have been met with the response “I just implemented that last night...”. See BDFL.