title: Comparison between DateField and date.today()
body: <p>I have a method inside a Django Model class for a Task, that must return the risk situation of such, based on the comparison of expected start and finish dates with today, but I get an error when I try to compare start_date and finish_date models.DateField with date.today()</p>
  
  <p>this is the code of the method:</p>
  
  <pre><code>def get_todo_situation(self):
      if self.finish_date == None:
          return 'unassigned'
      elif date.today() &lt; self.start_date:
          return 'warning'
      elif date.today() &lt; self.finish_date:
          return 'danger'
      else:
          return 'normal'
  </code></pre>
  
  <p>and this is the error I get:</p>
  
  <pre><code> File "/home/hugolvc/Code/TaskManagerProject/TaskManager/TaskManagerApp/models.py", line 63, in get_todo_situation
  elif date.today() &lt; self.start_date:
  TypeError: '&lt;' not supported between instances of 'datetime.date' and 'NoneType'
  </code></pre>
  
  <p>I have seen examples where this works, but I think I am failing to grasp something.</p>