def test_change_radius(self):
x = 20
y = 20
radius = 6
marker = Marker(x, y, radius)
new_radius = 12
marker.radius = new_radius
assert_that(marker.circle.radius, equal_to(new_radius))
assert_that(marker.left_hair.get_xdata(), equal_to((8, 14)))
assert_that(marker.left_hair.get_ydata(), equal_to((20, 20)))
assert_that(marker.right_hair.get_xdata(), equal_to((26, 32)))
assert_that(marker.right_hair.get_ydata(), equal_to((20, 20)))
assert_that(marker.top_hair.get_xdata(), equal_to((20, 20)))
assert_that(marker.top_hair.get_ydata(), equal_to((26, 32)))
assert_that(marker.bottom_hair.get_xdata(), equal_to((20, 20)))
assert_that(marker.bottom_hair.get_ydata(), equal_to((8, 14)))
