code: def forward(self, x: paddle.Tensor) -> paddle.Tensor:
      u = x.mean(1, keepdim=True)
      s = (x - u).pow(2).mean(1, keepdim=True)
      x = (x - u) / paddle.sqrt(s + self.eps)
      x = (
          self.weight[:, (None), (None)] * x
          + self.bias[:, (None), (None)]
      )
      return x
  
file_path: PaddleSeg/contrib/SegmentAnything/segment_anything/modeling/common.py
imports: import paddle
  import paddle.nn
  from typing import Type
label_desc: Use image node_id 2 for calling the LayerNorm2d obj's underlying member method code with example usage: obj.forward(x) and returns: x