def _get_values(self, action, arg_strings):
        # for everything but PARSER args, strip out '--'
        if [PARSER, REMAINDER] not in action.nargs:
            arg_strings = [s for s in arg_strings if s != '--']

        # optional argument produces a default when not present
        if not arg_strings and action.nargs == OPTIONAL:
            if action.option_strings:
                value = action.const
            else:
                value = action.default
            if isinstance(value, basestring):
                value = self._get_value(action, value)
                self._check_value(action, value)

        # when nargs='*' on a positional, if there were no command-line
        # args, use the default if it is anything other than None
        elif (not arg_strings and action.nargs == ZERO_OR_MORE and
              not action.option_strings):
            if action.default is not None:
                value = action.default
            else:
                value = arg_strings
            self._check_value(action, value)

        # single argument or optional argument produces a single value
        elif len(arg_strings) == 1 and action.nargs in [None, OPTIONAL]:
            arg_string, = arg_strings
            value = self._get_value(action, arg_string)
            self._check_value(action, value)

        # REMAINDER arguments convert all values, checking none
        elif action.nargs == REMAINDER:
            value = [self._get_value(action, v) for v in arg_strings]

        # PARSER arguments convert all values, but check only the first
        elif action.nargs == PARSER:
            value = [self._get_value(action, v) for v in arg_strings]
            self._check_value(action, value[0])

        # all other types of nargs produce a list
        else:
            value = [self._get_value(action, v) for v in arg_strings]
            for v in value:
                self._check_value(action, v)

        # return the converted value
        return value
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/argparse/argparse.py/ArgumentParser._get_values/swapped operands of `not in`