Python: unable to inherit from a C extension.

Posted by celil on Stack Overflow See other posts from Stack Overflow or by celil
Published on 2010-04-04T04:02:30Z Indexed on 2010/04/04 4:13 UTC
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Filed under:

python

|

inheritance

|

extension

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pysparse

I am trying to add a few extra methods to a matrix type from the pysparse library. Apart from that I want the new class to behave exactly like the original, so I chose to implement the changes using inheritance. However, when I try

from pysparse import spmatrix

class ll_mat(spmatrix.ll_mat):
    pass

this results in the following error

TypeError: Error when calling the metaclass bases
    cannot create 'builtin_function_or_method' instances

What is this causing this error? Is there a way to use delegation so that my new class behaves exactly the same way as the original?

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