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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_propagate(self, req: Request, sender: str):
 """ Add the specified request to the list of received PROPAGATEs. :param req: the REQUEST to add :param sender: the name of the node sending the msg """

        data = self.add(req)
        data.propagates[sender] = req