Part 3

canvas=getscreen()
canvas.num1= ""
canvas.operator=""
canvas.num1_done= False
canvas.num2= ""
canvas.num2_done= False

#This function will help you to click and write numbers & symbols
def use_calculator(x,y):
    if canvas.num1_done == False:
        if x>-80 and x<-50 and y>10 and y<40:
            canvas.num1 += "7"
        elif x>-40 and x<-10 and y>10 and y<40:
            canvas.num1 += "8"
        elif x>0 and x<30 and y>10 and y<40: 
            canvas.num1+= "9"
        elif x>-80 and x<-50 and y>-30 and y<0:
            canvas.num1 += "4"
        elif x>-40 and x<-10 and y>-30 and y<0: 
            canvas.num1+= "5"
        elif x>0 and x<30 and y>-30 and y<0:
            canvas.num1 += "6"
        elif x>-80 and x<-50 and y>-70 and y<-40: 
            canvas.num1+= "1"
        elif x>-40 and x<-10 and y>-60 and y<-30:
            canvas.num1 += "2"
        elif x>0 and x<30 and y>-60 and y<-30: 
            canvas.num1+= "3"
        elif x>0 and x<30 and y>-110 and y<-80:
            canvas.num1 += "0"
        elif x>40 and x<70 and y>-110 and y<-90:
            canvas.num1_done = True
            canvas.operator ="+"
        elif x>40 and x<70 and y>-70 and y<-40:
            canvas.num1_done = True
            canvas.operator = "-"
        elif x>40 and x<70 and y>-30 and y<0:
            canvas.num1_done = True 
            canvas.operator ="x"
        elif x>40 and x<70 and y>10 and y<40:
            canvas.num1_done = True
            canvas.operator = "/"
    
        seth(0)
        draw_screen()
        penup()
        goto(80,80)
        color("black")
        pendown()
        write(canvas.num1 + "" + canvas.operator, font=("Arial", 10), align="right")
    
    elif canvas.num2_done == False: 
        if x>-80 and x<-50 and y>10 and y<40: 
            canvas.num2 += "7"
        elif x>-40 and x<-10 and y>10 and y<40:
            canvas.num2 += "8"
        elif x>0 and x<30 and y>10 and y<40: 
            canvas.num2+= "9"
        elif x>-80 and x<-50 and y>-30 and y<0:
            canvas.num2 += "4"
        elif x>-40 and x<-10 and y>-30 and y<0: 
            canvas.num2+= "5"
        elif x>0 and x<30 and y>-30 and y<0:
            canvas.num2 += "6"
        elif x>-80 and x<-50 and y>-70 and y<-40: 
            canvas.num2+= "1"
        elif x>-40 and x<-10 and y>-60 and y<-30:
            canvas.num2 += "2"
        elif x>0 and x<30 and y>-60 and y<-30: 
            canvas.num2+= "3"
        elif x>0 and x<30 and y>-110 and y<-80:
            canvas.num2 += "0"
        
        elif x>40 and x<70 and y>-110 and y<-90:
            canvas.num2_done = True
            canvas.operator ="+"
        elif x>40 and x<70 and y>-70 and y<-40:
            canvas.num2_done = True
            canvas.operator = "-"
        elif x>40 and x<70 and y>-30 and y<0:
            canvas.num2_done = True 
            canvas.operator ="x"
        elif x>40 and x<70 and y>10 and y<40:
            canvas.num2_done = True
            canvas.operator = "/"
        seth(0)
        draw_screen()
        penup()
        goto(80,80)
        color("black")
        pendown()
        write(canvas.num1 + "" + canvas.operator + "" + canvas.num2[, font=("Arial", 10), align="right")
     
#Calls the function to use calculator    
canvas.onclick(use_calculator)