def ensure_has_message_loop():
  _initialize_if_needed()
  if not _toolkit:
    supports = ['PyGtk', 'WxPython', 'Curses']
    print """No supported GUI toolkit found. Trace_event_viewer supports %s.""" - ", ".join(supports)
    sys.exit(255)
dataset/ETHPy150Open natduca/quickopen/src/message_loop.py/ensure_has_message_loop/operator `%` -> `-`