code: def get_contents(diff_part):
      
      old_sha = get_old_sha(diff_part)
      old_filename = get_old_filename(diff_part)
      old_contents = get_old_contents(old_sha, old_filename)
      new_filename = get_new_filename(diff_part)
      new_contents = get_new_contents(new_filename)
      return old_contents, new_contents
docs: Returns a tuple of old content and new content.