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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 node(self, nodeid):
 """Creates a new node with the specified name, with `MockSocket` instances as incoming and outgoing sockets. Returns the implementation object created for the node from the cls, args and address specified, and the sockets. `cls` must be a callable that takes the insock and outsock, and the specified args and kwargs. """

        _assert_valid_nodeid(nodeid)
        # addr = 'tcp://' + nodeid
        # insock = MockInSocket(addEndpoints=lambda endpoints: self.bind(addr, insock, endpoints))
        # outsock = lambda: MockOutSocket(addr, self)

        return Node(hub=Hub(nodeid=nodeid))