code: def GenerateLibSig(short_name):
    
    with _UTILITY_LOCK:
      utilities_used = ', '.join([utility for utility
                                  in sorted(_utility_registry)])
      _utility_registry.Clear()
  
    if utilities_used:
      return ' (%s, %s, %s, %s)' % (short_name, _COMMON_LIB_SIG, _PYTHON_VERSION,
                                    utilities_used)
    else:
      return ' (%s, %s, %s)' % (short_name, _COMMON_LIB_SIG, _PYTHON_VERSION)
docs: Generates a library signature suitable for a user agent field.
  
    Args:
      short_name: The short, product-specific string name for the library.
    Returns:
      A library signature string to append to user-supplied user-agent value.