title: Calculate time span in Python
body: <p>im using Python v2.x on Windows 64bit</p>
  
  <p>I would like to record two moments in real time and calculate the time span.
  Please see code as following:</p>
  
  <pre><code>current_time1 = datetime.datetime.now().time() # first moment
  
  # ... some statement...some loops...take some time...
  
  current_time2 = datetime.datetime.now().time() # second moment
  
  time_span = current_time1 - current_time2
  </code></pre>
  
  <p>Apparently the last line is not executable because current_time is not integer, so my question is, how to convert this statement to integer to do the math? Convert to seconds is my first thought... </p>