<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(argv=None):
 """ben-nett entry point"""

    arguments = cli_common(__doc__, argv=argv)
    benet = BeNet(arguments['CAMPAIGN_FILE'])
    benet.run()
    if argv is not None:
        return benet