title: Django: Limiting or excluding choices in a tuple for modelchoices
body: <p>I am seeking assistance regarding this matter, I am trying to limit or exclude choices in the <code>APPLICANT_DATA</code> or is it even possible? The data is displayed only in the admin.</p>
  
  <pre><code>APPLICANT_STAT = (
      (0, 'For Initial Interview'),
      (1, 'For Intial Exam'),
      (2, 'For Final Interview'),
      (3, 'For Training'),
      (4, 'For Evaluation Exam'),
      (5, 'For Evaluation'),
      (6, 'HIRED'),
      (7, 'FAILED'),
      (8, 'Fired/Retired'),
  )
  class APPLICANT_DATA(models.Model):
      APP_STATUS =  models.IntegerField(choices=APPLICANT_STAT, default=0)
  </code></pre>
  
  <p>Something like this to limit the choices:</p>
  
  <pre><code>APP_STATUS =  models.IntegerField(choices=APPLICANT_STAT[0][5], default=0)
  #does not work obviously
  </code></pre>
  
  <p>Or is there another way like limiting it in the admin field? Thanks in advance.</p>