code: def left_button_press(self, obj, event):
      # print("Left Button pressed")
      self.OnLeftButtonDown()
      return
  
imports: import vtk
  import json
  import numpy
  import argparse
  import sys
  import subprocess
  from plyfile import PlyData
label_desc: Use image node_id 4 for calling the MyEvent obj's underlying member method code with example usage: obj.left_button_press(obj, event) without return types