sample triangle class

triangle.py

class C:
    def __init__(self, x, y):
        self.x = x
        self.y = y
    def __repr__(self):
        return f"({self.x}, {self.y})"
    def __sub__(self, other):
        return ((self.x - other.x) ** 2 + (self.y - other.y) ** 2) ** 0.5


class Triangle:
    def __init__(self, coords):
        self.p1 = C(*coords[0])
        self.p2 = C(*coords[1])
        self.p3 = C(*coords[2])
        self.calc_ratios()
    l1 = property(lambda self: self.p2 - self.p1)
    l2 = property(lambda self: self.p3 - self.p2) 
    l3 = property(lambda self: self.p1 - self.p3) 
    def calc_ratios(self):
        sides = sorted([self.l1, self.l2, self.l3])
        self.ratios = sides[1] / sides[0], sides[2] / sides[0]
    def __eq__(self, other):
        if not isinstance(other, Triangle):
            return False
        return all(math.isclose(self.ratios[i], other.ratios[i], rel_tol=0.001) for i in (0, 1))
    def __repr__(self):
        return f"Triangle ([{(self.p1, self.p2, self.p3)}])"