title: Converting a custom date format (string) to a datetime
body: <p>I have a large set (100+ million) of observations with the date represented as a custom string format. We did not generate the date strings, I just need to convert the date string to a datetime type. </p>
  
  <p>How do I convert a string date (eg, 12 JUN 2010) to a datetime? My thoughts are to parse the string into components, assemble them in the correct order, and pass that string to the constructor of datetime. Is there a way to pass datetime() a custom date format string instead?</p>
  
  <p>Thanks!</p>