code: def update(self, name=None, description=None, privacy_policy=None,
                 subscription_policy=None, is_managed=None):
          
          with db.session.begin_nested():
              if name is not None:
                  self.name = name
              if description is not None:
                  self.description = description
              if (
                  privacy_policy is not None and
                  PrivacyPolicy.validate(privacy_policy)
              ):
                  self.privacy_policy = privacy_policy
              if (
                  subscription_policy is not None and
                  SubscriptionPolicy.validate(subscription_policy)
              ):
                  self.subscription_policy = subscription_policy
              if is_managed is not None:
                  self.is_managed = is_managed
  
              db.session.merge(self)
  
          return self
docs: Update group.
  
          :param name: Name of group.
          :param description: Description of group.
          :param privacy_policy: PrivacyPolicy
          :param subscription_policy: SubscriptionPolicy
          :returns: Updated group