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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 add_nodes(self, nodes):
 """ Add a given node or list of nodes to self.node_list. Args: node (Node or list[Node]):
 the node or list of nodes to add to the graph Returns: None Examples: Adding one node: :: ['One'] Adding multiple nodes at a time in a list: :: ['One', 'Two'] """

        # Generalize nodes to a list
        if not isinstance(nodes, list):
            add_list = [nodes]
        else:
            add_list = nodes
        self.node_list.extend(add_list)