code: def _fuse_conv_bn(conv, bn):
      """fuse conv and bn for train or eval"""
      assert (
          conv.training == bn.training
      ), "Conv and BN both must be in the same mode (train or eval)."
      if conv.training:
          assert (
              bn._num_features == conv._out_channels
          ), "Output channel of Conv2d must match num_features of BatchNorm2d"
          raise NotImplementedError
      else:
          return _fuse_conv_bn_eval(conv, bn)
  
file_path: PaddleDetection/ppdet/utils/fuse_utils.py
imports: import copy
  import paddle
  import paddle.nn
label_desc: Use image node_id 5 for calling a global function with example usage: _fuse_conv_bn(conv, bn) and returns: _fuse_conv_bn_eval