title: Sum of elements stored inside a tuple
body: <p>Given a tuple containing a bunch of integer elements, how can one find the sum of all the elements?</p>
  
  <p>For example, if I have a list of tuples:</p>
  
  <pre><code>li = [(1, 2), (1, 3), (2, 3)]
  </code></pre>
  
  <p>How can I get something like this:</p>
  
  <pre><code>[3, 4, 5]
  </code></pre>
  
  <p>where 3, 4 and 5 is the total sum of each of the three tuples respectively?</p>