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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 wait_for_start(self):
 """ Wait for the RabbitMQ process to be come up. """

        er = self.exec_rabbitmqctl(
            'wait', ['--pid', '1', '--timeout', str(int(self.wait_timeout))])
        output_lines(er, error_exc=TimeoutError)