Evaluate the `output` with the critic then uses `self.loss_funcG` to combine it with `target`.

def generator(self, output, target):
        "Evaluate the `output` with the critic then uses `self.loss_funcG` to combine it with `target`."
        fake_pred = self.gan_model.critic(output)
        return self.loss_funcG(fake_pred, target, output)