old_contents: from tkinter import *
  import os
  root = Tk()
  def regular(file):
      os.system(file)
  Button(root, text='Regular Edit', command=regular("start.py")).pack(side=LEFT)
  Button(root, text='WYSIWYG', command=regular("startw.py")).pack(side= RIGHT)
  
  root.mainloop()
  
new_contents: from tkinter import *
  import os
  root = Tk()
  def regular(file):
      os.system(file)
  Button(root, text='Regular Edit', command=regular("nonWysiwyg.py")).pack(side=LEFT)
  Button(root, text='WYSIWYG', command=regular("wysiwyg.py")).pack(side= RIGHT)
  
  root.mainloop()
  
subject: Update load.py