title: Python: how to update list with zero values?
body: <p>I am new to python and would appreciate if anyone could help me with this.
  I have a list of values as following:</p>
  
  <pre><code>('1', '3', '4')
  ('43', '3', '2')
  ('49', '3', '3')
  ('59', '3', '4')
  ('62', '3', '3')
  ('63', '3', '2')
  </code></pre>
  
  <p>and so on..
  first column is for user id. This list is in ascending order of user id's.
  There are missing users in between consecutive rows. I would like to fill these missing values with consecutive numbers (userid) and zeros for other columns. e.g.-</p>
  
  <pre><code>('1', '3', '4')
  ('2', '0', '0')
  ('3', '0', '0')
  ('4', '0', '0')
  
  .
  .
  ('47', '0', '0')
  ('48', '0', '0')
  ('49', '3', '3')
  ('50', '0', '0')
  .
  
  .
  ('59', '3', '4')
  .
  .
  ('62', '3', '3')
  ('63', '3', '2')
  </code></pre>
  
  <p>and so on...
  Any help would be greatly appreciated. Thanks.</p>