Types de données en Python - LMPT

Troisième exemple
from tkinter import *
def cercle(can, x, y, r):
can.create_oval(x-r,y-r,x+r,y+r)
class Application(Tk):
def __init__(self):
Tk.__init__(self)
self.can=Canvas(self, width=475, height=130, bg=’white’)
self.can.pack(side=TOP, padx=5, pady=5)
Button(self, text="Train", command=self.dessine).pack(side=LEFT)
Button(self, text="Hello", command=self.coucou).pack(side=LEFT)
def dessine(self):
self.w1=Wagon(self.can, 10, 30)
self.w2=Wagon(self.can, 130, 30)
self.w3=Wagon(self.can, 250, 30)
self.w4=Wagon(self.can, 370, 30)
def coucou(self):
self.w1.perso(3)
self.w1.perso(1)
self.w1.perso(2)
self.w1.perso(1)
class Wagon(object):
def __init__(self, canev, x,y):
self.canev, self.x, self.y = canev, x, y
canev.create_rectangle(x,y,x+95,y+60)
for xf in range(x+5,x+90,30):
canev.create_rectangle(xf,y+5,xf+25,y+40)
cercle(canev, x+18, y+73, 12)
cercle(canev, x+77, y+73, 12)
def perso(self, fen):
xf = self.x + fen*30 - 12
yf = self.y + 25
cercle(self.canev, xf, yf, 10)
cercle(self.canev, xf-5, yf-3, 2)
cercle(self.canev, xf+5, yf-3, 2)
cercle(self.canev, xf, yf+5, 3)
app = Application()
app.mainloop()