title: Python markdown add class to table
body: <p>I use markdown extantions: <code>['nl2br', 'tables', 'attr_list']</code></p>
  
  <p>I need make tables 3 types, like example, standart, blocks and prices. But then i try do this with <strong>attr_list</strong> i have nothing..</p>
  
  <p><img src="https://monosnap.com/image/igmSsVAefCXzoJIhvcPyAbZn3VKrr1.png" alt="Alt text"></p>
  
  <p>And have something like this:</p>
  
  <p><img src="https://monosnap.com/image/UAacbWkRjkzlZDLLIIK1T120KEU7Eg.png" alt="Alt text"></p>
  
  <p>Question: how add class to whole table, using extention, if this possible?</p>