Yes, the code is shown as

for batch_idx, (imgs, pids, _) in enumerate(trainloader):
‘’'some train code
if (batch_idx + 1) % args.print_freq == 0:
print(‘Epoch: [{0}][{1}/{2}]\t’
‘Time {batch_time.val:.3f} ({batch_time.avg:.3f})\t’
‘Data {data_time.val:.4f} ({data_time.avg:.4f})\t’
‘Loss {loss.val:.4f} ({loss.avg:.4f})\t’.format(
epoch + 1, batch_idx + 1, len(trainloader), batch_time=batch_time,
data_time=data_time, loss=losses))

and the trainloader is defined as

trainloader = DataLoader(
ImageDataset(dataset.train, transform=transform_train),
sampler=RandomIdentitySampler(dataset.train, args.train_batch, args.num_instances),
batch_size=args.train_batch, num_workers=args.workers,
pin_memory=pin_memory, drop_last=True,
)

The batchsize is set to be 128, and there are about 150k samples in dataset.