On Friday, January 8, 2016 at 12:44:01 PM UTC-5, Robert wrote: > Hi, > > Thanks Ian for replying to my previous post. Here is a further question on > the 'return' line below. > > > > > import collections > import pickle > class C(collections.defaultdict): > def __init__(self): > collections.defaultdict.__init__(self, list) > def __reduce__(self): > t = collections.defaultdict.__reduce__(self) > return (t[0], ()) + t[2:] > > > c=C() > print c > print c.__reduce__() > c[1].append(200) > c[2].append(223) > c2 = pickle.loads(pickle.dumps(c)) > c2 == c > /////////// > From below command, I see 't' should be a tuple: > > > c.__reduce__() > Out[103]: (__main__.C, (), None, None, <dictionary-itemiterator at 0xaa0dd68>) > > > Then, I cannot get the idea what the two level parenthesis are for. > Its result is a tuple? Then, it can add 't[2:]'. > > return (t[0], ()) + t[2:] > > > It is not a tuple because there is no third level parenthesis, i.e. > > ((t[0], ()) + t[2:]) > > > Do you have a simple way for me to make it clear? Thanks,
OK. I get my answer for it. It is a tuple. I should get familiar with the return line. Thanks, -- https://mail.python.org/mailman/listinfo/python-list
