title: Increasing the counter in a list every two elements
body: <p>I have a list of elements:</p>
  
  <pre><code>list = ['elem1', 'elem2', 'elem3', 'elem4', 'elem5']
  </code></pre>
  
  <p>which I use in pairs in this way:</p>
  
  <pre><code>for x in range(0, len(list)-1):
      print(list[x], list[x+1])
  </code></pre>
  
  <p>This works and returns:</p>
  
  <pre><code>('elem1', 'elem2')
  ('elem2', 'elem3')
  ('elem3', 'elem4')
  ('elem4', 'elem5')
  </code></pre>
  
  <p>I would like to increase a counter every time I print a row. How can I do this?</p>