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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 new_message(self):
 """ creates a new message, setting `type`, `source`, `ts`, `data` - `data` is initialized to an empty array """

        msg = {}
        msg['data'] = []
        msg['type'] = self.plugin_type
        msg['source'] = self.name
        msg['ts'] = (datetime.datetime.utcnow() - datetime.datetime(1970, 1, 1)).total_seconds()
        return msg