Python selenium pickle错误

如果我使用selenium==2.41.0并尝试pickle数据，我会遇到下一个问题：

TypeError: a float is required pickle

转储/加载selenium驱动程序的代码：

with open(fn, 'wb') as out:
    pickle.dump(driver, out, pickle.HIGHEST_PROTOCOL)

with open(fn, 'rb') as inp:
    self.driver = pickle.load(inp)

如果i user selenium==2.37.2，则一切正常