'Update a service provider.
:param sp_id: id of the service provider
:type sp_id: string
:param sp: service prvider object
:type sp: dict
:returns: service provider ref
:rtype: dict
:raises keystone.exception.ServiceProviderNotFound: If the service
provider doesn\'t exist.'

@abc.abstractmethod
def update_sp(self, sp_id, sp):

    raise exception.NotImplemented()
