title: How do I reference the first index of lists of lists?
body: <p>I've written the code below:</p>
  <pre><code>items = [[1,91],[1,92],[2,93],[2,97],[1,60],[2,77],[1,65],[1,87],[1,100],[2,100],[2,76]]
  
  sorted_items = sorted(items, key=lambda x: x[0])
  
  for i in sorted_items:
      if i[0] == (i+1)[0]: 
  </code></pre>
  <p>The above code gives me an error- particularly for the last line of code. My question is, how do I reference the first index of lists within lists? I hope the question is clear from the last line of my code.</p>
  <p>i.e. i[0] is okay, but Python doesn't allow (i+1)[0]; how else can I write this?</p>
  <p>Thanks.</p>
  <p>Just a follow on from my question above:</p>
  <pre><code>for i in range(len(sorted_items)-1):
      if sorted_items[i][0] == sorted_items[i+1][0]:
          final_sorted_items = sorted(sorted_items, key=lambda x:x[1], reverse=True)
  
  print(final_sorted_items)
  </code></pre>
  <p>So I have added the line but it doesn't do the job that I am after. I basically want to sort the smaller lists in descending order if the first index is the same. Any idea how to amend my code to do this? Cheers</p>