title: how to find element by css selector using python / selenium
body: <p>i'm trying to pick up links of youtube channels which are located as below:</p>
  
  <pre><code>&lt;a id="author-text" class="yt-simple-endpoint style-scope ytd-comment- 
  renderer" href="/channel/UCUSy-h1fPG1L6X7KOe70asA"&gt; &lt;span class="style- 
  scope ytd-comment-renderer"&gt;Jörgen Nilsson&lt;/span&gt;&lt;/a&gt;
  </code></pre>
  
  <p>So in the example above I would want to pick up "/channel/UCUSy-h1fPG1L6X7KOe70asA". So far i have tried many options but none work:</p>
  
  <pre><code>driver = webdriver.Chrome('C:/Users/me/Chrome Web Driver/chromedriver.exe')
  api_url="https://www.youtube.com/watch?v=TQG7m1BFeRc"
  driver.get(api_url)
  time.sleep(2) 
  div = driver.find_element_by_class_name("yt-simple-endpoint style-scope ytd-comment-renderer")
  </code></pre>
  
  <p>but I get the following error:
      InvalidSelectorException: Message: invalid selector: Compound class names not permitted</p>
  
  <p>I also tried other approaches:</p>
  
  <pre><code>div = driver.find_elements_by_xpath("yt-simple-endpoint style-scope ytd-comment-renderer")
  
  div = driver.find_element_by_class_name('yt-simple-endpoint style-scope ytd-comment-renderer')
  
  div=driver.find_element_by_css_selector('.yt-simple-endpoint style-scope ytd-comment-renderer').get_attribute('href')
  </code></pre>
  
  <p>but no luck.. if someone could please help it would be much appreciated. Thank you</p>