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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 serialize_dict(self, msg_dict):
 """Serialize to JSON a message dictionary."""

        serialized = json.dumps(msg_dict, namedtuple_as_object=False)
        if PY2:
            serialized = serialized.decode("utf-8")
        serialized = "{}\nend\n".format(serialized)
        return serialized