A = (4, 1)
B = (6, 1)
C = (6, 2)
D = (4, 2)
poly1, a, b, c, d = Polygon(A, B, C, D)
E = (6, 5)
F = (4, 5)
poly2, a_1, b_1, e, f = Polygon(A, B, E, F)
G = (7, 1)
H = (10, 1)
I = (10, 2)
J = (7, 2)
poly3, g, h, i, j = Polygon(G, H, I, J)
K = (10, 10)
L = (7, 10)
poly4, g_1, h_1, k, l = Polygon(G, H, K, L)