TypeError: argument of type 'NoneType' is not iterable

[Huizhaoaaaa]

I get the following error when I run download.py print(type(args.datasets)) <class 'NoneType'> Why is this error? How to modify,？Thank you for correcting！ ERROR: File "", line 1, in runfile('D:/python/SSGAN-Tensorflow/download.py', wdir='D:/python/SSGAN-Tensorflow')

File "D:\cpsoftware\Ananconda\envs\opencv\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 827, in runfile execfile(filename, namespace)

File "D:\cpsoftware\Ananconda\envs\opencv\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 110, in execfile exec(compile(f.read(), filename, 'exec'), namespace)

File "D:/python/SSGAN-Tensorflow/download.py", line 184, in if 'MNIST' in args.datasets:

TypeError: argument of type 'NoneType' is not iterable