Yes, but sys.version_info isn't a namedtuple (which are in fact tuples), it's the (sort-of) C equivalent, which isn't a real tuple.

>>> from collections import namedtuple
>>> x = namedtuple('x', 'a b c')
>>> '%s %s %s' % x(1, 2, 3)
'1 2 3'

Hmm, but sys.version_info is a tuple:
>>> isinstance(sys.version_info, tuple)
True

I'll have to check if PyTuple_Check returns true or not. Maybe the problem is in the mapping check.

I'll investigate more.