def _get_validation_loss(self):
    try:
        validation_loss = self._get_validation_loss_()
    except StopIteration:
        self.validation_loader_it = iter(self.validation_loader)
        validation_loss = self._get_validation_loss_()
    return validation_loss
def _get_validation_loss(self):
    try:
        validation_loss = self._get_validation_loss_()
    except StopIteration:
        self.validation_loader_it = iter(self.validation_loader)
        validation_loss = self._get_validation_loss_()
    return validation_loss