因为它是Java. Python的文档位于此处.

Because that's Java. Python's documentation is here.

有一个名为set_window_size的方法，该方法定义为

There's a method called set_window_size, which is defined here:

driver.set_window_size(1400,1000)

进一步阅读:如何使用Selenium WebDriver获取窗口大小，调整窗口大小或最大化窗口