When I try to run app.py (Python 3.3, PyCrypto 2.6) my virtualenv keeps returning the error listed above. My import statement is just from Crypto.Cipher import AES
To date, I'm having same issue when importing from Crypto.Cipher import AES even when I've installed/reinstalled pycrypto a few times. End up it's because pip defaulted to python3.
~ pip --version
pip 18.0 from /usr/local/lib/python3.7/site-packages/pip (python 3.7)
installing pycrypto with pip2 should solve this issue.