safeframe.py

from selenium import webdriver
from selenium.webdriver import DesiredCapabilities
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

user_agent = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.57 Safari/537.36"

dcap = dict(DesiredCapabilities.PHANTOMJS)
dcap["phantomjs.page.settings.userAgent"] = user_agent

driver = webdriver.PhantomJS(desired_capabilities=dcap)
driver.get("http://express.co.uk/")

wait = WebDriverWait(driver, 10)
wait.until(EC.visibility_of_element_located((By.CSS_SELECTOR, ".single-category")))

# loop through all the frames
for index, frame in enumerate(driver.find_elements_by_css_selector("iframe")):
    is_safe = frame.get_attribute("data-is-safeframe") == "true"
    if is_safe:
        print(frame.get_attribute("outerHTML"))
        driver.switch_to.frame(index)
        print(driver.page_source)
        driver.switch_to.default_content()
        print("----------")

driver.close()