title: Multiply two multi-dimension lists
body: <p>For example, </p>
  
  <pre><code>Price = [['1', '5'], ['4', '9']]
  
  Quantity = [['50.00', '0'], ['10.00', '20.00']]
  </code></pre>
  
  <p>want to  have </p>
  
  <pre><code>Revenue = [['50.00', '0'], ['40.00', '180.00']]
  </code></pre>
  
  <p>Tried using list comprehension, but don't know how it works for this two-dimension lists.</p>