cannot create my own dict

[A.T.Hofkamp]

Hello all,

This morning I tried to create my own read-only dictionary, and failed
miserably.
I don't understand why, can somebody enlighten me?

Below is a brute-force experiment that cannot deal with "x in obj", plz read
the explanation below the code:
--------------------------------
class myowndict(object):
    def __init__(self, mydict):
        self.mydict = mydict

# Below is produced with
# print '\n'.join(['        self.%s = self.mydict.%s' % (v,v)
#                                         for v in dir(dict)])
# commented-out functions done by hand
#
        #self.__class__ = self.mydict.__class__
        self.__cmp__ = self.mydict.__cmp__
        self.__contains__ = self.mydict.__contains__
        self.__delattr__ = self.mydict.__delattr__
        self.__delitem__ = self.mydict.__delitem__
        #self.__doc__ = self.mydict.__doc__
        self.__eq__ = self.mydict.__eq__
        self.__ge__ = self.mydict.__ge__
        self.__getattribute__ = self.mydict.__getattribute__
        self.__getitem__ = self.mydict.__getitem__
        self.__gt__ = self.mydict.__gt__
        self.__hash__ = self.mydict.__hash__
        #self.__init__ = self.mydict.__init__
        self.__iter__ = self.mydict.__iter__
        self.__le__ = self.mydict.__le__
        self.__len__ = self.mydict.__len__
        self.__lt__ = self.mydict.__lt__
        self.__ne__ = self.mydict.__ne__
        #self.__new__ = self.mydict.__new__
        self.__reduce__ = self.mydict.__reduce__
        self.__reduce_ex__ = self.mydict.__reduce_ex__
        self.__repr__ = self.mydict.__repr__
        self.__setattr__ = self.mydict.__setattr__
        self.__setitem__ = self.mydict.__setitem__
        self.__str__ = self.mydict.__str__
        self.clear = self.mydict.clear
        self.copy = self.mydict.copy
        self.fromkeys = self.mydict.fromkeys
        self.get = self.mydict.get
        self.has_key = self.mydict.has_key
        self.items = self.mydict.items
        self.iteritems = self.mydict.iteritems
        self.iterkeys = self.mydict.iterkeys
        self.itervalues = self.mydict.itervalues
        self.keys = self.mydict.keys
        self.pop = self.mydict.pop
        self.popitem = self.mydict.popitem
        self.setdefault = self.mydict.setdefault
        self.update = self.mydict.update
        self.values = self.mydict.values

        # end of __init__

if __name__ == '__main__':
    fd = myowndict({1:10})
    print 1 in fd  # FAILS! (with "TypeError: iterable argument required")
--------------------------------

I wanted to make my own dictionary. However, a simple element test failed
(after implementing various __*__ functions), and I cannot figure out why.

The above code is a brute force attempt, where I forward all methods (except
__class__, __doc__, __init__, and __new__) to my local 'mydict' object.

IT STILL FAILS.

So if copying all methods of a native dictionary is not enough, what should I
do to make my class work as a dictionary WITHOUT deriving from dict (which will
obviously work).



Sincerely,
Albert