Ilya,

The exception "TypeError: cafile should be a valid filesystem path" is raised by Python, not by OpenSSL. On Python 3.5, PyUnicode_FSConverter() uses MBCS, which is CP-1552 on your system. CP-1552 cannot convert Arabic character set and fails to encode your user name to bytes. This issue has been addressed by PEP 529 in Python 3.6. Starting with Python 3.6, the file system encoding is UTF-8, see https://www.python.org/dev/peps/pep-0529/

3.5 is in security fix-only mode. You either have to keep encoding the path as UTF-8 explicitly or update to Python 3.6. I'm closing this issue was WONTFIX 3.5 and FIXED >= 3.6.