code: def fuse_bn(conv: nn.Module, bn: nn.Module):
      """
      Fuse conv & bn modules.
      """
      kernel = conv.weight
      running_mean = bn.running_mean
      running_var = bn.running_var
      gamma = bn.weight
      beta = bn.bias
      eps = bn.eps
      std = (running_var + eps).sqrt()
      t = (gamma / std).reshape(-1, 1, 1, 1)
      return kernel * t, beta - running_mean * gamma / std
  
imports: from torch import nn
  from towhee.models.layers.droppath import DropPath
  from towhee.models.layers.conv_bn_activation import Conv2dBNActivation
label_desc: Use image node_id 1 for calling a global function with example usage: fuse_bn(conv, bn) and returns: unknown,  unknown