class_docstr: A layer that gets fed its answers from an upstream connection,
  for instance from a component earlier in the pipeline.
code: def __init__(self, upstream_name: str):
      Model.__init__(
          self, name=self.name, forward=forward, dims={"nO": None}
      )
      self.upstream_name = upstream_name
      self._batch_id = None
      self._outputs = None
      self._backprop = None
  
file_path: spacy-transformers/spacy_transformers/layers/listener.py
imports: from typing import Optional, Callable, List
  from thinc.api import Model
  from spacy.errors import Errors
  from spacy.tokens import Doc
  from ..data_classes import TransformerData
label_desc: Use image node_id 1 to create a new TransformerListener object from inherited base classes: Model with example: obj = TransformerListener(upstream_name)