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overriding equals operation

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I am trying to define class, where if I use a statement a = b, then instead of "a" pointing to the same instance as "b", it should point to a copy of "b", but I can't get it right.

Currently, I have the following:

----

class myclass(object):
        def __init__(self, name='')
                self.name = name

        def copy(self):
                newvar = myclass(self.name)
                return newvar

        def __eq__(self, other):
                if instance(other, myclass):
                        return self == other.copy()
                return NotImplemented
----

Now if I try:

>>> a=myclass()
>>> a.name = 'test'
>>> b=a
>>> b.name
'test'
>>> b.name = 'test2'
>>> a.name
'test2'

I wanted b=a to make a new copy of "a", but then when I assigned b.name = 'test2', even a.name became 'test2'.

How can I rectify my code to make the __eq__() behave like copy()?

Thanks


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overriding equals operation Pradipto Banerjee <pradipto.banerjee@adainvestments.com> - 2012-10-16 08:51 -0500
  Re: overriding equals operation Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2012-10-16 16:07 +0200
  Re: overriding equals operation Nobody <nobody@nowhere.com> - 2012-10-16 18:31 +0100
  Re: overriding equals operation 88888 Dihedral <dihedral88888@googlemail.com> - 2012-10-16 21:16 -0700
    Re: overriding equals operation Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-10-17 09:14 +0100
  Re: overriding equals operation 88888 Dihedral <dihedral88888@googlemail.com> - 2012-10-16 21:16 -0700

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