import tkinter as tk
window = tk.Tk()
canvas = tk.Canvas(window)
canvas.pack()
#Tkinter has an arrow option in the create_line method. tk.Last specifies the position at which
#the arrow is placed, in this case the last coordinate set of the line, hence "LAST".
canvas.create_line(0, 0, 200, 100, arrow=tk.LAST)
window.mainloop()