def _PrintHelpAndExit(self, exit_code=2):
    self.parser.print_help()
    sys.exit(exit_code)
From http://stackoverflow.com/questions/136168/get-last-n-lines-of-a-file-with-python-similar-to-tail
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/tools/appcfg.py/AppCfgApp._PrintHelpAndExit--crossover with--dataset/ETHPy150Open cowrie/cowrie/cowrie/core/utils.py/tail