os.chmod can be used to update the permissions of a file or directory. Here is the minimal boilterplate code without error handling. It's important to use 0o for the leading zero due to how this handles octets.

#!/usr/bin/python3
import os
os.chmod(f"/path/to/file", 0o775)

Here is a more practical example, with try/except/else error handling.

#!/usr/bin/python3
import os

try:
  os.chmod(f"/path/to/file", 0o775)
except Exception as exception:
  print(f"Got the following exception when attempting to update /path/to/file to mode -rwxrwxr-x (0775) - {exception}")
else:
  print(f"Successfully updated /path/to/file to mode -rwxrwxr-x (0775)")