title: Purpose of the initial variable in list comprehension
body: <pre><code> evens_to_50 = [i for i in range(51) if i % 2 == 0]
   print evens_to_50
  </code></pre>
  
  <p>Can someone explain the <strong>i</strong> that stands directly after the closed bracket and before the <strong>for</strong> in the first row of this code, or share a link or a guide that explains such codes; All I found is a general explanation (not for python, but programmering in general) but nothing too specific; I understand (I think) how the <strong>for i in range(51) if i % 2 == 0</strong> but not the <strong>i</strong> part before it. </p>