Tks @harmonyliu, its works for me. U save my day.

[emafra]

I think there is some dependency bug in the source code (version azure-storage-blob==2.1.0 ) of blockblobservice.py and init.py under site-packages/azure/storage/blob/ directory. Because when I type in
from azure.storage.blob.blockblobservice import BlockBlobService
it worked.

Originally posted by @harmonyliu in #389 (comment)