title: How to click on the play button of a youtube video embedded within smtebook through selenium and python
body: <p>I want click the youtube play in <a href="https://smtebooks.us/downfile/13192/building-serverless-python-web-services-zappa-pdf" rel="nofollow noreferrer">https://smtebooks.us/downfile/13192/building-serverless-python-web-services-zappa-pdf</a></p>
  
  <p>my code is :</p>
  
  <pre><code>browser.switch_to.frame(0) 
  element = browser.find_element_by_xpath("//button[@class='ytp-large-play-button ytp-button']")
  element.click()
  </code></pre>
  
  <p>but can not find element</p>
  
  <pre><code>selenium.common.exceptions.NoSuchElementException: Message: no such element: Unable to locate element: {"method":"xpath","selector":"//button[@class='ytp-large-play-button ytp-button']"}
  (Session info: chrome=67.0.3396.99)
  (Driver info: chromedriver=2.37.543627 (63642262d9fb93fb4ab52398be4286d844092a5e),platform=Windows NT 10.0.17134 x86_64)
  </code></pre>
  
  <p>Anyone have some idea how to deal with it ?</p>
  
  <p>Thank you!</p>