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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 to_dict(self):
 """Returns a simplified dictionary representing the Graph. Returns: A dictionary that can easily be serialized to JSON. """

    return {
        "node": [v.to_dict() for v in self.vertices],
        "edge": [e.to_dict() for e in self.edges]
    }