def test_sphere_init():
s1 = Sphere(6)
assert type(s1) is Sphere
assert s1.radius == 6
assert s1.diameter == 6 * 2
s2 = Sphere.from_diameter(3)
assert type(s2) is Sphere
def test_ing_sphere_classmethod(self):
i = random.randint(0,50)
j = random.randint(51,100)
c1 = Sphere.from_diameter(i)
self.assertEqual(eval(repr(c1)), Sphere(i/2))