title: How to apply progressbar for the original indexes?
body: <p>I would like to use the <code>progressbar</code> module and I use this method:</p>
  
  <pre><code>bar = progressbar.ProgressBar(maxval=len(c)).start()
  for i,idx in enumerate(c):
       # do something
       bar.update(idx)
  </code></pre>
  
  <p>Unfortunately, in my case I can not use <code>enumerate</code>, because my list<code>c</code> is in the form <code>[0,1,4,5,7,9]</code> and I need to keep the original values, and I would like to index <code>for i in c</code>. Because indexes from the list <code>c</code> speak about elements from another list, which should be searched yet. And the <code>for-loop</code> is inside the <code>while-loop</code> where the <code>c</code> list is different at every new step.
  How to deal with this? Maybe different progressbar?</p>