I have a function that resembles the one below. I'm not sure how to use the os module to get back to my original working directory at the conclusion of the jar's execution.
owd = os.getcwd()
#first change dir to build_dir path
#run jar from test directory
#change dir back to original working directory (owd)
You simply need to add the line:
Just a note this was also answered in your other question.