text: from tkinter import *
  from tkinter.ttk import *
  
  class DomainTree(Treeview):
  
     def __init__(self, master = None):
        super().__init__()
  
     def populateTree():
        pass
  
  class DomainApp(Frame):
  
     def __init__(self, master=None):
        super().__init__()
        self.pack()
  
        self.tree = DomainTree(master = self)
        self.tree['columns'] = ('count')
        self.tree.pack(fill = 'both', expand = True)
  
  
  if __name__ == '__main__':
     root = Tk()
     app = DomainApp(master = root)
     root.mainloop()
     root.destroy()
  