code: def forward(self, img1, img2, flow, valid):
      return self.transforms(img1, img2, flow, valid)
  
file_path: vision/references/optical_flow/presets.py
imports: import torch
  import transforms
label_desc: Use image node_id 2 for calling the OpticalFlowPresetTrain obj's underlying member method code with example usage: obj.forward(img1, img2, flow, valid) and returns: self