title: Pandas: filter dataframe per group with condition matching at least one item in group
body: <p>I have dataframe</p>
  
  <pre><code>ID   url   session
  111   facebook.com   1
  111   vk.com   1
  111   stackoverflow.com   2
  222   wsj.com  3
  222   ria.ru   3
  222   twitter.com   4
  333   wikipedia.org   5
  333   rt.com   5
  </code></pre>
  
  <p>I need to get session, if there are a valid urls</p>
  
  <pre><code>valid_urls = ['rt.com', 'wsj.com']
  </code></pre>
  
  <p>Desire output</p>
  
  <pre><code>ID   url   session
  222   wsj.com  3
  222   ria.ru   3
  333   wikipedia.org   5
  333   rt.com   5
  </code></pre>
  
  <p>I know, that I can filter using <code>df.url.str.contains</code>, but how can I add there condition with <code>session</code>?</p>