appendix gturtlescreen methods method description screen update(perform turtlescreen update screen window_height(return the height of the turtle window example (for turtlescreen instance named screen)screen window_height( screen window_width(return the width of the turtle window example (for turtlescreen instance named screen)screen window_width( screen mainloop(starts event loop calling tkinter' mainloop function must be last statement in turtle graphics program must not be used if script is run from within idle in - mode (no subprocessfor interactive use of turtle graphics example (for turtlescreen instance named screen)screen mainloop(screen numinput(titlepromptdefault=noneminval=nonemaxval=nonepop up dialog window for input of number argumentstitle is the title of the dialog windowprompt is text mostly describing what numerical information to input defaultdefault value minvalminimum value for imput maxvalmaximum value for input the number input must be in the range minval maxval if these are given if nota hint is issued and the dialog remains open for correction return the number input if the dialog is canceledreturn none example (for turtlescreen instance named screen)screen numinput("poker""your stakes:" minval= maxval= screen textinput(titlepromptpop up dialog window for input of string argumentstitle is the title of the dialog windowprompt is text mostly describing what information to input return the string input if the dialog is canceledreturn none example (for turtlescreen instance named screen)screen textinput("nim""name of first player:"this copy belongs to 'acha