AttributeError: 'ConcatDataset' object has no attribute 'img_norm_cfg'

[ZSX2018]

when i run test.py, there is an error:
File "tools/test.py", line 211, in
main()
File "tools/test.py", line 181, in main
outputs = single_gpu_test(model, data_loader, args.show, args.log_dir)
File "tools/test.py", line 39, in single_gpu_test
model.module.show_result(data, result, dataset.img_norm_cfg, dataset='DOTA1_5')
AttributeError: 'ConcatDataset' object has no attribute 'img_norm_cfg'

How can I solve this problem?