def test_rotation_about_origin():
origin = Point(0, 0)
point = Point(1, 1)
assert point.rotate_about(origin, 90) == Point(-1, 1)
assert point.rotate_about(origin, 45) == Point(0, math.sqrt(2))
assert point.rotate_about(origin, 180) == Point(-1, -1)
def test_rotation_about_simple():
about = Point(1, 1)
point = Point(1, 2)
assert point.rotate_about(about, 90) == Point(0, 1)
assert point.rotate_about(about, 180) == Point(1, 0)