text: from utils import show_error, cbox, open_data, plot_region, tk, window
  
  tk.Tk.report_callback_exception = show_error
  
  tk.Button(text='Open file', command=open_data).pack()
  tk.Button(text='Plot', command=plot_region).pack()
  
  cbox.pack()
  
  window.mainloop()
  