self.current_model = None self.metamodel = None self.toolbar_frame = tk.Frame(self) self.canvas_frame = tk.Frame(self) self.progressbar_frame = tk.Frame(self) self.toolbar_frame.pack(fill=tk.X) self.canvas_frame.pack(fill=tk.BOTH, expand=tk.TRUE) self.progressbar_frame.pack(fill=tk.X) self.destroy()