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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(self, transport, address=None):
 """ add a new recipient to be addressable by this MessageDispatcher generate a new uuid address if one is not specified """


        if not address:
            address = str(uuid.uuid1())

        if address in self.recipients:
            self.recipients[address].add(transport)
        else:
            self.recipients[address] = RecipientManager(transport, address)

        return address