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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_link_to_self(self, source, weight):
 """ Create and add a ``Link`` from a source node to ``self``. Args: source (Node):
 The node that will own the new ``Link`` pointing to ``self`` weight (int or float):
 The weight of the newly created ``Link`` Returns: None Example: One 5 node.Link instance pointing to node with value "One" with weight 5 """

        # Generalize source to a list to simplify code
        if not isinstance(source, list):
            source = [source]
        for source_node in source:
            source_node.add_link(self, weight=weight)