title: Perl or Python: Convert date from dd/mm/yyyy to yyyy-mm-dd
body: <p>I have lots of dates in a column in a CSV file that I need to convert from dd/mm/yyyy to yyyy-mm-dd format.  For example 17/01/2010 should be converted to 2010-01-17. </p>
  
  <p>How can I do this in Perl or Python?</p>