title: Convert encoded date values to Datetime
body: <p>I have encoded values for Day(0,6), Month(1,12), Week(1,52) and the year is 2014 in a list. I need these encoded values to be transformed into a datetime object/string date in python. </p>
  
  <p>For example, </p>
  
  <pre><code>Day Week Month
  6   3    1   
  </code></pre>
  
  <p>This must then been transformed to "2014-01-18"</p>