def __repr__(self):
        args = [self._mode, self._bufsize]
        args_str = ', '.join([repr(arg) for arg in args if arg is not None])
        return (type(self).__name__, args_str) % '%s(%s)'

# ===========================
# Optional and Positional Parsing
# ===========================
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/argparse/argparse.py/FileType.__repr__/swapped operands of `%`