code: def to_json(self):
          
  
          result = super(ContentType, self).to_json()
          result.update({
              'name': self.name,
              'description': self.description,
              'displayField': self.display_field,
              'fields': [f.to_json() for f in self.fields]
          })
          return result
docs: Returns the JSON representation of the content type.