ERROR: Could not build wheels for cryptography which use PEP 517 and cannot be installed directly
Setting cryptography to version 2.8 in requirements.txt fixed the issue.
TLDR;
Try using cryptography==3.1.1
Details:
This happened on Python 3.9.0 on Windows 10 PC.I had the following in requirements.txt
cryptography==2.8I removed the version and kept only cryptography in requirements.txt file like below
cryptographySaved the requirements.txt and then I ran
pip install -r requirements.txtIt installed successfully.Then I freeze the requirements.txt by running the following command
pip freeze > requirements.txtThen the requirements.txt got updated with cryptography==3.1.1
Had also this issue. If you're using alpine, make sure that all dependencies for cryptography are installed.In my case the cargo package was missing and causing the issue.
sudo apk add gcc musl-dev python3-dev libffi-dev openssl-dev cargohttps://cryptography.io/en/latest/installation.html#building-cryptography-on-linux