docstr: Schemes are the pre-defined network architectures of various depths and complexities that can be used for the
  InputEmbedder. Should be implemented in child classes, and are used to create Block when InputEmbedder is
  initialised.
  
  :return: dictionary of schemes, with key of type EmbedderScheme enum and value being list of mxnet.gluon.Block.
code: def schemes(self) -> dict:
      """
      Schemes are the pre-defined network architectures of various depths and complexities that can be used for the
      InputEmbedder. Should be implemented in child classes, and are used to create Block when InputEmbedder is
      initialised.
  
      :return: dictionary of schemes, with key of type EmbedderScheme enum and value being list of mxnet.gluon.Block.
      """
      raise NotImplementedError(
          "Inheriting embedder must define schemes matching its allowed default "
          "configurations."
      )
  
file_path: coach/rl_coach/architectures/mxnet_components/embedders/embedder.py
imports: from typing import Union
  from types import ModuleType
  import mxnet
  from mxnet.gluon import nn
  from rl_coach.architectures.embedder_parameters import InputEmbedderParameters
  from rl_coach.architectures.mxnet_components.layers import convert_layer
  from rl_coach.base_parameters import EmbedderScheme
label_desc: Use image node_id 2 for calling the InputEmbedder obj's underlying member method code with example usage: obj.schemes() without return types