GlideinWMS

The current code base has a mixed use of str(), .encode and .decode that seem at times inconsistent.
Paths are created at times adding strings or formatting them.
Some conversions are not needed, str() over bytes causes wrong representations, mixing types can cause errors.

Use of functions like

os.path.join(path, *paths)
# (path-like, *path-like) -> str

or strings (str, unicode strings) should be encouraged

The code should be inspected (file opening, ...)

Here a specification of path-like and path handling
https://www.python.org/dev/peps/pep-0519/

These posts talk about possible errors (but are not completely useful):
https://www.btelligent.com/en/blog/best-practice-working-with-paths-in-python-part-1/
https://www.btelligent.com/en/blog/best-practice-working-with-paths-in-python-part-2/