Writes training and validation batch images to Tensorboard.

def write(self, learn:Learner, trn_batch:Tuple, val_batch:Tuple, iteration:int, tbwriter:SummaryWriter)->None:
        "Writes training and validation batch images to Tensorboard."
        self._write_for_dstype(learn=learn, batch=val_batch, iteration=iteration, tbwriter=tbwriter, ds_type=DatasetType.Valid)
        self._write_for_dstype(learn=learn, batch=trn_batch, iteration=iteration, tbwriter=tbwriter, ds_type=DatasetType.Train)