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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def index(self):
 """Retrieve the attribute index number. Args:: no argument Returns:: attribute index number (starting at 0) C library equivalent : SDfindattr """


        self._index = _C.SDfindattr(self._obj._id, self._name)
        _checkErr('find', self._index, 'illegal attribute name')
        return self._index