def Parse(self, argument):
    if self.enum_values and self.enum_values not in argument:
      raise ValueError("value should be one of <%s>" %
                       "|".join(self.enum_values))
    return argument
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/python-gflags/gflags.py/EnumParser.Parse/swapped operands of `not in`