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From: Walter Brameld IV on 17 Apr 2010 10:26
vsoler wrote:
> I have the following script:
>
> class TTT(object):
> def duplica(self):
> self.data *= 2
> def __init__(self, data):
> self.data = data
> TTT.duplica(self.data)
> def __str__(self):
> return str(self.data)
>
> print
> obj=TTT(7)
> print obj
>
> And I want 14 printed (twice 7)
>
> I got the following error:
> TypeError: unbound method duplica() must be called with TTT instance
> as first argument (got int instance instead)
>
> What am I doing wrong?

duplica() takes a 'self' parameter (a TTT instance), but you're calling
it with self.data (an int instance). Change this line:

TTT.duplica(self.data)

to this:

TTT.duplica(self)

and it will do what you want.
From: Walter Brameld IV on 17 Apr 2010 10:26
vsoler wrote:
> I have the following script:
>
> class TTT(object):
> def duplica(self):
> self.data *= 2
> def __init__(self, data):
> self.data = data
> TTT.duplica(self.data)
> def __str__(self):
> return str(self.data)
>
> print
> obj=TTT(7)
> print obj
>
> And I want 14 printed (twice 7)
>
> I got the following error:
> TypeError: unbound method duplica() must be called with TTT instance
> as first argument (got int instance instead)
>
> What am I doing wrong?

duplica() takes a 'self' parameter (a TTT instance), but you're calling
it with self.data (an int instance). Change this line:

TTT.duplica(self.data)

to this:

TTT.duplica(self)

and it will do what you want.
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