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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 socket(self, socket_type, identity=None, mechanism=None):
 """ Create and register a new socket. :param socket_type: The type of the socket. :param loop: An optional event loop to associate the socket with. This is the preferred method to create new sockets. """

        socket = Socket(
            context=self,
            socket_type=socket_type,
            identity=identity,
            mechanism=mechanism,
            loop=self.loop,
        )
        self.register_child(socket)
        return socket