title: Python: Unpacking an inner nested tuple/list while still getting its index number
body: <p>I am familiar with using <code>enumerate()</code>:</p>
  
  <pre><code>&gt;&gt;&gt; seq_flat = ('A', 'B', 'C')
  &gt;&gt;&gt; for num, entry in enumerate(seq_flat):
          print num, entry
  0 A
  1 B
  2 C
  </code></pre>
  
  <p>I want to be able to do the same for a nested list:</p>
  
  <pre><code>&gt;&gt;&gt; seq_nested = (('A', 'Apple'), ('B', 'Boat'), ('C', 'Cat'))
  </code></pre>
  
  <p>I can unpack it with:</p>
  
  <pre><code>&gt;&gt;&gt; for letter, word in seq_nested:
          print letter, word
  A Apple
  B Boat
  C Cat
  </code></pre>
  
  <p>How should I unpack it to get the following?</p>
  
  <pre><code>0 A Apple
  1 B Boat
  2 C Cat
  </code></pre>
  
  <p>The only way I know is to use a counter/incrementor, which is un-Pythonic as far as I know. Is there a more elegant way to do it?</p>