Selenium WebDriver- 指定頁面加載時間

#encoding=utf-8
import unittest
import time
from selenium import webdriver
from selenium.webdriver import ActionChains
from selenium.common.exceptions import TimeoutException
from selenium.webdriver.common.keys import Keys


class setPageLoadTime(unittest.TestCase):
    def setUp(self):
        # 啟動火狐瀏覽器
        self.driver = webdriver.Ie(executable_path = "e:\\IEDriverServer")

    def test_PageLoadTime(self):
        # 設定頁面加載限制時間為4秒
        self.driver.set_page_load_timeout(4)
        self.driver.maximize_window()
        try:
            startTime = time.time()
            self.driver.get("http://mail.126.com")
        except TimeoutException:
            print u'頁面加載超過設定時間，超時'
            # 當頁面加載時間超過設定時間，
            # 通過執行Javascript來stop加載，然后繼續執行后續動作
            self.driver.execute_script('window.stop()')
        end = time.time() - startTime
        print end
        # 切換進frame控件
        self.driver.switch_to.frame("x-URS-iframe")
        # 獲取用戶名輸入框
        userName = self.driver.find_element_by_xpath('//input[@name="email"]')
        # 輸入用戶名
        userName.send_keys("xxx")
        # 獲取密碼輸入框
        pwd = self.driver.find_element_by_xpath("//input[@name='password']")
        # 輸入密碼
        pwd.send_keys("xxx")
        # 發送一個回車鍵
        pwd.send_keys(Keys.RETURN)
        time.sleep(5)
    assert u"退出" in self.driver.page_source

    def tearDown(self):
        self.driver.quit()

if __name__ == '__main__':
    unittest.main()