title: How to find the name of a list in a list of lists instead of its value?
body: <p>I am trying to find the name of a list in a list of lists (is there a specific name for "list of lists"?).</p>
  
  <p>For example I have the following lists:</p>
  
  <pre><code>x= ["a","b"]
  y= ["c","d"]
  z= [x,y] 
  </code></pre>
  
  <p>If I now want to know what is the name of the first list in list "z" I would try like that:</p>
  
  <pre><code>print(z[0])
  </code></pre>
  
  <p>But instead of "x" I get the value of x ("a","b")</p>
  
  <ul>
  <li>How can I get the output "x"? </li>
  </ul>