draw.rect(window, WHITE, (x1, y1, x2-x1, y2-y1), 2)
draw.line(window, WHITE, [x1+h, y1], [x1+h, y2], 2)
draw.line(window, WHITE, [x1+2*h, y1], [x1+2*h, y2], 2)
draw.line(window, WHITE, [x1+3*h, y1], [x1+3*h, y2], 2)
...
x1 = 100; y1 = 100
x2 = 300; y2 = 200
N = 10
draw.rect(window, WHITE, (x1, y1, x2-x1, y2-y1), 2)
h = (x2-x1)/(N+1)
x = x1 + h
for i in range(N):
draw.line(window, WHITE, [x, y1], [x, y2], 2)
x +=h
draw.line(window, WHITE, [x1+h, y1], [x1+h-а, y2], 2)
draw.line(window, WHITE, [x1+2*h, y1], [x1+2*h-а, y2], 2)
draw.line(window, WHITE, [x1+3*h, y1], [x1+3*h-а, y2], 2)
...
draw.line(window, WHITE, [x1, y1+hy], [x1+hx, y1+hy], 2)
draw.line(window, WHITE, [x1, y1+2*hy], [x1+2*hx, y1+2*hy], 2)
draw.line(window, WHITE, [x1, y1+3*hy], [x1+3*hx, y1+3*hy], 2)
...