Основа Пакмана. Создать движение и проверку. Условия

s=tk.Canvas(window,width=500,height=500,background="#ffc0ff") 
 
def go(dx,dy): 
 s.move("zmey",dx,dy) 
 s.update() 
 
def zmey(x,y): 
 s.create_oval(x+80,y+80,x+120,y+ 120, fill="green",tag="zmey") 
 
def eda(x2,y2): 
 s.create_oval(x2,y2,x2+10,y2+10, fill="yellow") 
 
 
def f(): 
 go(10,10) 
 if (x2-x)**2+(y2-y)**2<(R+r)**2: 
 return 
 window.after(500,lambda:f()) 
 
f() 
 
 
eda(300,300) 
zmey(0,0) 
 
 
window.bind("<d>",lambda event: go(10,0)) 
window.bind("<a>",lambda event: go(-10,0)) 
window.bind("<s>",lambda event: go(0,10)) 
window.bind("<w>",lambda event: go(0,-10)) 
 
 
s.pack() 
window.mainloop()

import tkinter as tk
 
window = tk.Tk()
s=tk.Canvas(window,width=500,height=500,background="#ffc0ff") 
 
dirs = {'right': (1,0), 'left': (-1,0), 'down': (0,1), 'up': (0,-1)}
direction = dirs['up']
 
def go():
 s.move("zmey", direction[0], direction[1]) 
 s.update() 
 window.after(100, go)
 
def zmey(x,y): 
 s.create_oval(x+80,y+80,x+120,y+ 120, fill="green",tag="zmey") 
 
def eda(x2,y2): 
 s.create_oval(x2,y2,x2+10,y2+10, fill="yellow") 
 
 
def set_direction(direct):
    global direction
    direction = dirs[direct]
 
# def f(): 
#  go(10,10) 
#  if (x2-x)**2+(y2-y)**2<(R+r)**2: 
#   return 
#  window.after(500,lambda:f()) 
 
# f() 
 
 
eda(300,300) 
zmey(0,0) 
 
window.bind("<d>",lambda event: set_direction('right')) 
window.bind("<a>",lambda event: set_direction('left')) 
window.bind("<s>",lambda event: set_direction('down')) 
window.bind("<w>",lambda event: set_direction('up')) 
 
s.pack() 
 
window.after(100, go) 
 
window.mainloop()