code: def original_layer_class():
      return BigBirdLayer
  
imports: from transformers.models.big_bird.modeling_big_bird import BigBirdLayer
  from parallelformers.policies.base import Layer, Policy
  from parallelformers.utils.dist_utils import AllReduceLinear
label_desc: Use image node_id 3 for calling the BigBirdPolicy obj's underlying member method code with example usage: obj.original_layer_class() and returns: BigBirdLayer