code: def get_layer_groups(self):
          
          return [
              [self.policy_backbone, self.action_head],
              [self.value_backbone, [y for (x, y) in self.critic_head.named_parameters() if x.endswith('bias')]],
              # OpenAI regularizes only weight on the last layer. I'm just replicating that
              [[y for (x, y) in self.critic_head.named_parameters() if x.endswith('weight')]]
          ]
docs: Return layers grouped