x = [ [1, 2, 3], [4, 5, 6], [7, 8, 9] ] y = [ [1, 2, 3], [4, 5, 6], [7, 8, 9] ] z = [] for i in range(3): for j in range(3): z.append(x[i][j] + y[i][j]) print(z)