How to handle single quote/ apostrophe and space together in linux cat command?

I have a file named test's file.txt inside test's dir directory. So the file-path becomes test's dir/test's file.txt. I want to cat the content of the file but since the file contains an apostrophe and a space it is giving me hard time achieving that. I have tried several commands including

1. sh -c "cat 'test's dir/test's file.txt'"
2. sh -c 'cat "test's dir/test's file.txt"'
3. sh -c "cat '"'"'test's dir/test's file.txt'"'"'"
4. sh -c 'cat "test\'s\ dir/test\'s\ file.txt"' and many more ... But none of them is working.

Would you please try:

sh -c "cat 'test'\''s dir/test'\''s file.txt'"

As for the pathname part, it is a concatenation of:

'test'
\'
's dir/test'
\'
's file.txt'

If you want to execute the shell command in python, would you please try:

#!/usr/bin/python3

import subprocess

path="test's dir/test's file.txt"
subprocess.run(['cat', path])

or immediately:

subprocess.run(['cat', "test's dir/test's file.txt"])

As the subprocess.run() function takes the command as a list, not a single string (possible with shell=True option), we do not have to worry about the extra quoting around the command.

Please note subprocess.run() is supported by Python 3.5 or newer.