python - ERROR: Could not build wheels for cryptography which use PEP 517 and cannot be installed directly

Question

I get an error when pip builds wheels for the cryptography package.

Error:

LINK : fatal error LNK1181: cannot open input file 'libssl.lib'
  error: command 'C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Tools\MSVC\14.16.27023\bin\HostX86\x86\link.exe' failed with exit status 1181
  ----------------------------------------
  ERROR: Failed building wheel for cryptography
  Running setup.py clean for cryptography
Failed to build cryptography
ERROR: Could not build wheels for cryptography which use PEP 517 and cannot be installed directly

I have already installed OpenSSL and set the environment variables as suggested in this post yet the problem persists. My setup details:

• System - Windows 10
• Python - 3.8
• Pip - 19.3.1

Answer 1

Setting cryptography to version 2.8 in requirements.txt fixed the issue.