title: Dates subtraction: has the event occurred or not?
body: <p>If I have everyday datetime - how to find out, the event has already occurred or not, by subtraction with <strong>datetime.now()</strong></p>
  
  <p>Let we had everyday meeting at 15:35. Today John came earlier - at 12:45, but Alex was late for 2 h. and 15 min. (came at 17:40).</p>
  
  <pre><code>meet_dt = datetime(year=2015, month=8, day=19, hour=15, minute=35)
  john_dt = datetime(year=2015, month=8, day=19, hour=12, minute=45)
  alex_dt = datetime(year=2015, month=8, day=19, hour=17, minute=40)
  
  print(meat_dt - john_dt) # came before &gt; 2:50:00
  print(meat_dt - alex_dt) # came after  &gt; -1 day, 21:55:00
  </code></pre>
  
  <p>If I take away from the big date less - then everything is fine, but conversely I recive <strong>-1 day, 21:55:00</strong> why not <strong>-2:15:00</strong>, what a minus day?</p>