def are_spheres_colliding(sphere_a, sphere_b):
	"""
	Return True if spheres are colliding.
	
	:param SphereCollider sphere_a: sphere a collider
	:param SphereCollider sphere_b: sphere b collider
	:return: True if spheres are colliding
	:rtype bool:
	"""
	return (sphere_a.center - sphere_b.center).length_squared() <= (sphere_a.radius + sphere_b.radius)**2