FWIW, at one point, Guido rejected all variants of the idea. His first
objection was that enumerate() is all about pairing values with
sequence indices, so starting from anything other than zero is in
conflict with the core concept. His second objection is that all
variants can easily be misread as starting at the nth item in the
sequence (much like islice() does now): enumerate(3, 'abcdefg') -->
(3,'d') (4,'e') (5, 'f') (6, 'g'). The latter mis-reading becomes more
likely for those who think of enumerate as providing indices. In fact,
one of the suggested names for enumerate was "indices".