Jay multiple open windows:

from selenium import webdriver
import time
d = webdriver.Firefox()
d.get("http://www.baidu.com")
d.find_element_by_id("kw").clear()
d.find_element_by_id("kw").send_keys("周杰伦")
d.find_element_by_id("su").click()
time.sleep(1)
d.find_element_by_partial_link_text("百度百科").click()
#查看Windows属性：
print(d.window_handles)
#查看Windows句柄：
print(d.current_window_handle)
d = webdriver.Firefox()
print(d.window_handles)
print(d.current_window_handle)
#按索引切换窗口：
d.switch_to_window(d.window_handles[1])