code: def window_partition_reverse(
      t: torch.Tensor, B: int, num_windows: int, C: int
  ) -> torch.Tensor:
      """
      Undo the @window_partition operation.
  
      Args:
          t: The input tensor of shape [batch_size * num_windows, window_size,
              embed_dim].
          B: The batch size.
          num_windows: The number of windows.
          C: The embedding dimension.
  
      Returns:
          A tensor of shape [batch_size, num_windows * window_size, embed_dim].
      """
      t = t.reshape(B, num_windows * t.shape[1], C)
      return t
  
file_path: ml-cvnets/cvnets/modules/windowed_transformer.py
imports: import argparse
  from typing import Optional, Tuple
  import torch
  from torch import Tensor
  from cvnets.layers import token_merging
  from cvnets.modules import transformer
label_desc: Use image node_id 2 for calling a global function with example usage: window_partition_reverse(t, B, num_windows, C) and returns: t