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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 disallow(nodes):
 """Decorator to disallow certain nodes from parsing. Raises a NotImplementedError instead. Returns ------- disallowed : callable """

    def disallowed(cls):
        cls.unsupported_nodes = ()
        for node in nodes:
            new_method = _node_not_implemented(node, cls)
            name = 'visit_{node}'.format(node=node)
            cls.unsupported_nodes += (name,)
            setattr(cls, name, new_method)
        return cls
    return disallowed