python - tkinter canvas in grid has extra space -

i have canvas inside frame , i've said canvas should 250x250. reason being created bigger, space on right , bottom. here's code... ideas?

from tkinter import * tkinter import ttk player import player0  alpha = ('a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z')  class gui(frame):      def __init__(self, master):         frame.__init__(self, master)         self.boardsize = 250         self.sqsize = self.boardsize//5         master.title("canvas space")         self.initialdraw()         self.grid(row=0,column=0)      def initialdraw(self):         mainframe = ttk.frame(self, padding=(5,5,5,5))         mainframe.grid(column=0, row=0, sticky=(n, s, e, w))          self.board = canvas(mainframe, width=self.boardsize, height=self.boardsize,bg='white')         self.board.grid(row=1,column=0)          row in range(5):             col in range(5):                 top = row * self.sqsize                 left = col * self.sqsize                 bottom = row * self.sqsize + self.sqsize -2                 right = col * self.sqsize + self.sqsize -2                 rect = self.board.create_rectangle(left,top,right,bottom,outline='gray',fill='')          self.board.focus_set()  if __name__ == '__main__':     tk = tk()     gui = gui(tk)     tk.mainloop() 

the result this:

i rather avoid white gutter on right , bottom of canvas after smaller squares have been drawn.

the canvas has border, controlled borderwidth attribute. has border controlled highlightthickness attribute. set both of 0 , canvas should size set be.

the border attribute typically used provide 3d effect -- raised border, sunken boarder, or couple other variations. highlightthickness (and highlightcolor) attributes define solid outline used denote widget has keyboard focus.