human
I wrote the below code

    from math import hypot, sqrt as _sqrt
    def rotatingCalipers(Points):
        (U, L) = convex_hull(*Points, **dict(polygon=False))
        if (L is None):
            if isinstance(U, Point):
                raise ValueError('At    least    two    distinct    points    must    be    given.')
            (yield U.args)
        else:
            i = 0
            j = (len(L) - 1)
            while ((i < (len(U) - 1)) or (j > 0)):
                (yield (U[i], L[j]))
                if (i == (len(U) - 1)):
                    j -= 1
                elif (j == 0):
                    i += 1
                elif (((U[(i + 1)].y - U[i].y) * (L[j].x - L[(j - 1)].x)) > ((L[j].y - L[(j - 1)].y) * (U[(i + 1)].x - U[i].x))):
                    i += 1
                else:
                    j -= 1
    p = [Point2D(i) for i in set(args)]
    if any(((not i.is_Rational) for j in p for i in j.args)):
        def hypot(x, y):
            arg = ((x * x) + (y * y))
            if arg.is_Rational:
                return _sqrt(arg)
            return sqrt(arg)
    rv = []
    diam = 0
    for pair in rotatingCalipers(args):
        (h, q) = _ordered_points(pair)
        d = hypot((h.x - q.x), (h.y - q.y))
        if (d > diam):
            rv = [(h, q)]
        elif (d == diam):
            rv.append((h, q))
        else:
            continue
        diam = d
    return set(rv)

What's a good function header?
assistant
#Here's a good function header.

def farthest_points(*args):