title: Normalise numbers in nested list
body: <p>I'm trying to normilise the second item in the below list to 1. I can do this if the list only has numbers in a single list as follows </p>
  
  <pre><code>rank = [['a', 234],['b',435],['c',567]]
  
  ranking = [float(i)/sum(rank) for i in rank]
  </code></pre>
  
  <p>However when the list has a second item and is nested this fails with </p>
  
  <pre><code>ranking = [float(i[1])/sum(rank) for i[1] in rank]
  </code></pre>