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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):
 """ Start all consumer processes and register signal handlers. """

        if self.huey.immediate:
            raise ConfigurationError(
                'Consumer cannot be run with Huey instances where immediate '
                'is enabled. Please check your configuration and ensure that '
                '"huey.immediate = False".')
        # Log startup message.
        self._logger.info('Huey consumer started with %s %s, PID %s at %s',
                          self.workers, self.worker_type, os.getpid(),
                          self.huey._get_timestamp())
        self._logger.info('Scheduler runs every %s second(s).',
                          self.scheduler_interval)
        self._logger.info('Periodic tasks are %s.',
                          'enabled' if self.periodic else 'disabled')

        self._set_signal_handlers()

        msg = ['The following commands are available:']
        for command in self.huey._registry._registry:
            msg.append('+ %s' % command)

        self._logger.info('\n'.join(msg))

        # We'll temporarily ignore SIGINT and SIGHUP (so that it is inherited
        # by the child-processes). Once the child processes are created, we
        # restore the handler.
        original_sigint_handler = signal.signal(signal.SIGINT, signal.SIG_IGN)
        if hasattr(signal, 'SIGHUP'):
            original_sighup_handler = signal.signal(signal.SIGHUP, signal.SIG_IGN)

        self.scheduler.start()
        for _, worker_process in self.worker_threads:
            worker_process.start()

        signal.signal(signal.SIGINT, original_sigint_handler)
        if hasattr(signal, 'SIGHUP'):
            signal.signal(signal.SIGHUP, original_sighup_handler)