title: How to add indices to a list?
body: <p>For example, I have a <code>list = ['a', 'b', 'c']</code>.<br>
  What I want is a list <code>indexed(list) == [(1, 'a'), (2, 'b'), (3, 'c)]</code>.</p>
  
  <p>Is there a builtin or module for this?</p>