code: def forward(
      self, feature_maps: List[Tensor]
  ) -> List[Tensor]:  # skipcq: PYL-W0221
      raise NotImplementedError
  
imports: import dataclasses
  from abc import abstractmethod
  from typing import Protocol, Tuple, List, Union, Mapping, Callable
  import numpy
  import torch.jit
  from torch import nn, Tensor
  from pytorch_toolbelt.utils import pytorch_toolbelt_deprecated
label_desc: Use image node_id 2 for calling the AbstractDecoder obj's underlying member method code with example usage: obj.forward(feature_maps) without return types