tuple([sequence])
Returns a tuple whose items are the same and in the same order
as sequence's items. The sequence argument may be a sequence, a
container that supports iteration, or an iterator object. If
sequence is already a tuple, it is returned unchanged. For
instance, tuple('abc') returns ('a', 'b',
'c') and tuple([1, 2, 3]) returns (1, 2,
3). If no argument is given, returns a new empty tuple,
().