code: def start(self):
      if (sys.flags.interactive != 1) or not hasattr(
          QtCore, "PYQT_VERSION"
      ):
          QtGui.QApplication.instance().exec_()
  
file_path: audio-spectrum-analyzer/pygraphGL_multsine.py
imports: from pyqtgraph.Qt import QtCore, QtGui
  import pyqtgraph.opengl
  import pyqtgraph
  import numpy
  import sys
  import time
label_desc: Use image node_id 2 for calling the Visualizer obj's underlying member method code with example usage: obj.start() without return types