code error in dataloader

[AlexanderTrg]

why here is train_dp_list?

train_loader = DataLoader(train_dp_list,
batch_sampler=BatchSamplerSimilarLength(dataset = train_dp_list,
batch_size=BATCH_SIZE),
collate_fn=collate_batch)
valid_loader = DataLoader(train_dp_list,
batch_sampler=BatchSamplerSimilarLength(dataset = valid_dp_list,
batch_size=BATCH_SIZE,
shuffle=False),
collate_fn=collate_batch)
test_loader = DataLoader(train_dp_list,
batch_sampler=BatchSamplerSimilarLength(dataset = test_dp_list,
batch_size=BATCH_SIZE,
shuffle=False),