A = np.array([[12, 3, 13, 6],
              [1, 15, 7, 5],
              [4, 11, 4, 8],
              [18, 2, 6, 8]])

print("hand-built:", det(A), "\t numpy:", np.linalg.det(A))
# hand-built: 6706    numpy: 6705.999999999999

        __
        __