class_docstr: Abstract base class for feature processor.
code: def forward(
      self,
      features: Dict[str, JaggedTensor],
  ) -> Dict[str, JaggedTensor]:
      pass
  
imports: import abc
  from collections import OrderedDict
  from typing import Any, Dict, Iterator, List, Optional, Tuple
  import torch
  import torch.nn
  from torchrec.fx.tracer import is_fx_tracing
  from torchrec.sparse.jagged_tensor import JaggedTensor, KeyedJaggedTensor
label_desc: Use image node_id 1 for calling the BaseFeatureProcessor obj's underlying member method code with example usage: obj.forward(features) without return types