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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 reader(self, sock, handler, arg):
 """ Register socket reader with the reactor. When the reader has messages, the reactor will call the handler, passing the arg. Returns 0 if OK, -1 if there was an error. If you register the same socket more than once, each instance will invoke its corresponding handler. """

        return lib.zloop_reader(self._as_parameter_, sock, handler, arg)