title: Sort an enumerated list by the value
body: <p>MWE:</p>
  
  <pre><code>list1 = [2,5,46,23,9,78]
  list1 = list(enumerate(list1))
  </code></pre>
  
  <p>Now suppose I want to sort this list by the index 1, i.e. by the original list1, in say, ascending order.
  How do I do that?</p>
  
  <p>I would like something that could then give me both the indexes and the values.</p>
  
  <pre><code>list2 = sorted(list1[1], key=float)
  </code></pre>