python tkinter button set variable to false -

i don't know set variable pressing button in python. example:

done = false ... range_button = button(self.parent, text="start", command=lambda.... ... while done:      ..... 

but don't know how in python, help?

there's nothing special doing tkinter -- if done global variable (or instance variable) set whatever value want. important part is, must non-local variable.

range_button = button(..., command=stop_loop)  def stop_root():     global done     done = true  def something_else():     global done     while !done:         ... 

strictly speaking, don't need global done statement in function loop, since function isn't changing value of variable. however, think makes intent of code little more evident.