• Is one dot missed? (for Heptagon)

Question related to mission Area of a Convex Polygon

 

I think the dot [9,4] is missed.

assert almost_equal(checkio([[4, 1], [3, 4], [3, 7], [4, 8], [7, 9], [9, 6], [7, 1]]), 35.5), "Heptagon"