code: def backward(ctx, grad_output):
      input, weight = ctx.saved_tensors
      (
          grad_input,
          grad_weight,
          grad_bias,
      ) = fused_dense_cuda.linear_bias_backward(
          input, weight, grad_output
      )
      return grad_input, grad_weight, grad_bias
  
imports: import torch
  from torch import nn
  import fused_dense_cuda
  from apex._autocast_utils import _cast_if_autocast_enabled
label_desc: Use image node_id 2 for calling the FusedDenseFunc obj's underlying member method code with example usage: obj.backward(ctx, grad_output) and returns: grad_input,  grad_weight,  grad_bias