class_docstr: BatchNorm2d where the batch statistics and the affine parameters are fixed
code: def forward(self, x):
      scale, bias = self.get_scale_bias(False)
      return x * scale + bias
  
imports: import functools
  import torch
  import torch.distributed
  from torch import nn
  from apex import check_cudnn_version_and_warn
  import fast_bottleneck
  import nccl_p2p_cuda
label_desc: Use image node_id 3 for calling the FrozenBatchNorm2d obj's underlying member method code with example usage: obj.forward(x) and returns: unknown