title: List of two elements tuples convert to list of tuples with the same elements
body: <p>I have list of 2-elements tuples:</p>
  
  <pre><code>[(7, 3), (4, 3), (5, 3), (6, 3), (0, 1), (1, 1), (2, 1), (3, 1)]
  </code></pre>
  
  <p>And I want to convert it to another list of tuples. Each list contains elements with the same second index from first list.</p>
  
  <p>So in this case result should look:</p>
  
  <pre><code>[(7, 4, 5, 6), (0, 1, 2, 3)]
  </code></pre>
  
  <p>because 7, 4, 5, and 6 are paired with 3 while 0, 1, 2, 3 are paired with 1.</p>
  
  <p>My attempt is to do it this way: </p>
  
  <blockquote>
    <p>x = list(map(operator.itemgetter(0), sorted_countries))</p>
  </blockquote>
  
  <p>but I still don't know how to group it, because my result is:</p>
  
  <pre><code>[7, 4, 5, 6, 0, 1, 2, 3]
  </code></pre>