docs: def _create_model(self, view_getter=None, source_getters=None,
                        model_factory=None, officer=None):
          """
          Creates a model from the model factory after retrieving
          the source and the view. The officer is the IOfficer
          FOR THE MODEL TO BE CREATED and NO OFFICER CHECKS ARE PERFORMED.
          """
  
          if view_getter is not None:
              d = defer.succeed(view_getter)
              d.addCallback(self._retrieve_view)
              d.addCallback(self._check_view)
          else:
              # views are inherited
              d = defer.succeed(self.model.view)
  
          d.addCallback(self._retrieve_model, source_getters,
                        model_factory, officer)
  
          d.addErrback(self._filter_errors)
          return d