sorry my question was not clear ,  what i mean after dividing fulldataset to val and training
train_size = int(0.8 * len(full_dataset))
val_size = len(full_dataset) - train_size
train_dataset, val_dataset = torch.utils.data.random_split(full_dataset, [train_size, val_size]
)```

`data augmentation supposed to happen after this point, or  after 



train_loader = data.DataLoader(train_dataset,shuffle=False,batch_size=bs)
val_loader = data.DataLoader(val_dataset,shuffle=False,batch_size=bs)