title: how convert list of int to list of tuples
body: <p>I want to convert a list like this</p>
  
  <pre><code>l1 = [1,2,3,4,5,6,7,8]
  </code></pre>
  
  <p>to</p>
  
  <pre><code>l2 = [(1,2),(3,4),(5,6),(7,8)]
  </code></pre>
  
  <p>because want to loop </p>
  
  <pre><code>for x,y in l2:
      draw_thing(x,y)
  </code></pre>