code: def forward(self, img_A, img_B):
      img = torch.cat((img_A, img_B), dim=1)
      conv_out = self.model(img)
      conv_out = conv_out.view(img_A.size(0), -1)
      prob = self.l1(conv_out)
      prob = F.sigmoid(prob)
      return prob
  
file_path: gans-with-pytorch/pix2pix/models.py
imports: import torch
  from torch import nn
  import torch.nn.functional
label_desc: Use image node_id 2 for calling the Discriminator obj's underlying member method code with example usage: obj.forward(img_A, img_B) and returns: prob