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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 unbind(self, handler, argspec):
 """ handler will no longer be called if args match argspec :param argspec: instance of ArgSpec - args to be matched """

        self.handlers[argspec.key].remove((handler, argspec))
        if not len(self.handlers[argspec.key]):
            del self.handlers[argspec.key]