title: Django-model: Save computed value in a model field
body: <p>I want to save the django model with computed field so that I can apply search on that.</p>
  
  <pre><code>class TestModel(models.Model):
      x = models.CharField(max_length=16)
      z = models.CharField(max_length=16)
  
      # I want a field like below and also saves in databse
      # computed =  computed()
  
      def computed(self):
          result = self.x + self.y
          return result
  </code></pre>