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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 start(self, fork=True):
 """Starts the registry aggregator. :param fork: whether to fork a process; if ``False``, blocks and stays in the existing process """

        if not fork:
            distributed_logger.info('Starting metrics aggregator, not forking')
            _registry_aggregator(self.reporter, self.socket_addr)
        else:
            distributed_logger.info('Starting metrics aggregator, forking')
            p = Process(target=_registry_aggregator, args=(self.reporter, self.socket_addr, ))
            p.start()
            distributed_logger.info('Started metrics aggregator as PID %s', p.pid)
            self.process = p