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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, exit=True):
        '''Called after forking to start the actor's life.

        This is where logging is configured, the :attr:`mailbox` is
        registered and the :attr:`_loop` is initialised and
        started. Calling this method more than once does nothing.
        '''
        if self.state == ACTOR_STATES.INITIAL:
            self._concurrency.before_start(self)
            self._concurrency.add_events(self)
            try:
                self.cfg.when_ready(self)
            except Exception:   # pragma    nocover
                self.logger.exception('Unhandled exception in when_ready hook')
            self._started = self._loop.time()
            self._exit = exit
            self.state = ACTOR_STATES.STARTING
            self._run()