Размещение виджет на Python

from tkinter import *
window = Tk()
canv = Canvas(window,width=500,height=500,bg="white")
 
lab_ent1 = Label(window,text="First point:")
ent1 = Entry(window,width=2)
lab_ent2 = Label(window,text="Second point:")
ent2 = Entry(window,width=2)
but_select = Button(window,text="Paths")
lab_minpath = Label(window,text="XXXXXX")
 
lab_list = Label(window,text="Graph:")
list_graphs = Listbox(window,selectmode=SINGLE,height=6)
but_all = Button(window,text="All graphs")
 
canv.grid(row=0,column=0,rowspan=40)
lab_ent1.grid(row=0,column=1,sticky=E,padx=10)
ent1.grid(row=0,column=2,sticky=W,padx=10)
lab_ent2.grid(row=1,column=1,sticky=E,padx=10)
ent2.grid(row=1,column=2,sticky=W,padx=10)
but_select.grid(row=2,column=1,columnspan=2,sticky=E+W,padx=10)
lab_minpath.grid(row=3,column=1,columnspan=2,sticky=N)
lab_list.grid(row=15,column=1,sticky=E+N,padx=10)
list_graphs.grid(row=15,column=2,sticky=W,padx=10)
but_all.grid(row=39,column=1,columnspan=2,sticky=E+W,padx=10)
window.mainloop()