class_docstr: DWT2D
class_docstr_tok: ["DWT2D"]
code: def forward(self, x):
      return DWTFunction.apply(
          x, self.w_ll, self.w_lh, self.w_hl, self.w_hh
      )
  
imports: import torch
  from torch import nn
  from torch.autograd import Function
  import pywt
  from functools import partial
label_desc: Use image node_id 2 for calling the DWT2D obj's underlying member method code with example usage: obj.forward(x) and returns: DWTFunction