code: def get_passphrase(passphrase=None):
      
      for passphrase_file_path in POTENTIAL_PASSPHRASE_LOCATIONS:
          if os.path.isfile(passphrase_file_path):
              with open(passphrase_file_path) as passphrase_file:
                  return passphrase_file.read()
      return passphrase
docs: Return a passphrase as found in a passphrase.ghost file
  
      Lookup is done in three locations on non-Windows systems and two on Windows
      All:
          `cwd/passphrase.ghost`
          `~/.ghost/passphrase.ghost`
      Only non-Windows:
          `/etc/ghost/passphrase.ghost`