def start(self):
        # Add a help command line argument if needed (i.e. -h and --help)
        self._add_help()
        # Add a version command line argument if needed (i.e. -v and --version)
        self._add_version()

        self._context['raw_args'] = sys.argv
        self._do_args(sys.argv[1:])

        if self._has_main:
            return self._main(self._context)
        return self._context
Called when the user wants to start processing command line arguments
dataset/ETHPy150Open kbknapp/Clapp-py/clapp/clapp.py/App.start