code: def get_or_add_user(self, user, **kwargs):
          
          is_admin = kwargs.pop("is_admin", False)
          users_count = self.users.all().count()
          if users_count == 0:
              is_admin = True
  
          org_user, created = self._org_user_model.objects.get_or_create(
              organization=self, user=user, defaults={"is_admin": is_admin}
          )
          if users_count == 0:
              self._org_owner_model.objects.create(
                  organization=self, organization_user=org_user
              )
          if created:
              # User added signal
              user_added.send(sender=self, user=user)
          return org_user, created
docs: Adds a new user to the organization, and if it's the first user makes
          the user an admin and the owner. Uses the `get_or_create` method to
          create or return the existing user.
  
          `user` should be a user instance, e.g. `auth.User`.
  
          Returns the same tuple as the `get_or_create` method, the
          `OrganizationUser` and a boolean value indicating whether the
          OrganizationUser was created or not.