code: def forward(self, x):
      shortcut = x
      x = self.norm1(x)
      # Window partition
      if self.window_size > 0:
          H, W = x.shape[1], x.shape[2]
          x, pad_hw = window_partition(x, self.window_size)
  
      x = self.attn(x)
      # Reverse window partition
      if self.window_size > 0:
          x = window_unpartition(x, self.window_size, pad_hw, (H, W))
  
      x = shortcut + self.drop_path(x)
      x = x + self.drop_path(self.mlp(self.norm2(x)))
  
      return x
  
imports: import math
  import torch
  import torch.nn
  import torch.nn.functional
  from mmcv.cnn import build_activation_layer, build_norm_layer
  from mmcv.cnn.bricks import DropPath
  from mmengine.logging import MMLogger
  from mmengine.model import BaseModule
  from mmengine.runner.checkpoint import CheckpointLoader
  from mmdet.registry import MODELS
label_desc: Use image node_id 2 for calling the Block obj's underlying member method code with example usage: obj.forward(x) and returns: x