<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def main():
 """ Run the simulation """

    parser = argparse.ArgumentParser(prog='opentrons_simulate',
                                     description=__doc__)
    parser.add_argument(
        'protocol', metavar='PROTOCOL_FILE',
        type=argparse.FileType('r'),
        help='The protocol file to simulate (specify - to read from stdin).')
    parser.add_argument(
        '-v', '--version', action='version',
        version=f'%(prog)s {opentrons.__version__}',
        help='Print the opentrons package version and exit')
    parser.add_argument(
        '-o', '--output', action='store',
        help='What to output during simulations',
        choices=['runlog', 'nothing'],
        default='runlog')
    parser.add_argument(
        '-l', '--log-level', action='store',
        help=('Log level for the opentrons stack. Anything below warning '
              'can be chatty'),
        choices=['error', 'warning', 'info', 'debug'],
        default='warning'
    )
    args = parser.parse_args()

    runlog = simulate(args.protocol, log_level=args.log_level)
    if args.output == 'runlog':
        print(format_runlog(runlog))
    return 0