I can do
from collections import namedtuple namedtuple('B', 'x y z')([1,2,3])
I get a TypeError: __new__() takes exactly 4 arguments (2 given) However I can do:
namedtuple('B', 'x y z')._make([1,2,3])
So namedtuple's _make classmethod looks a lot like tuple's __new__(). What's the rationale for this? Wouldn't it be better to share the same signature for __new__?
IPython's serialization code depends on a tuple's __new__() having the signature that tuple has and therefore does not work with namedtuples. See discussion here: http://article.gmane.org/gmane.comp.python.general/726849