class_docstr: GAN-based SVS model abstract class.
docstr: Return generator or discriminator loss.
docstr_tok: ["Return","generator","or","discriminator","loss","."]
code: def forward(
      self,
      forward_generator,
      *args,
      **kwargs,
  ) -> Dict[str, Union[torch.Tensor, Dict[str, torch.Tensor], int]]:
      """Return generator or discriminator loss."""
      raise NotImplementedError
  
imports: from abc import ABC, abstractmethod
  from typing import Dict, Union
  import torch
  from espnet2.svs.abs_svs import AbsSVS
label_desc: Use image node_id 1 for calling the AbsGANSVS obj's underlying member method code with example usage: obj.forward(forward_generator) without return types