title: Python datetime add
body: <p>I have a datetime value in string format. How can I change the format from a "-" separated date to a "." separated date. I also need to add 6 hours to let the data be in my time zone.</p>
  
  <pre><code>s = '2013-08-11 09:48:49'
  from datetime import datetime,timedelta
  mytime = datetime.strptime(s,"%Y-%m-%d %H:%M:%S")
  time = mytime.strftime("%Y.%m.%d %H:%M:%S")
  dt = str(timedelta(minutes=6*60))  #6 hours
  time+=dt
  print time
  print dt
  </code></pre>
  
  <p>I get the following result where it adds the six hours at the end and not to the nine:</p>
  
  <pre><code>2013.08.11 09:48:496:00:00
  6:00:00
  </code></pre>