'Add an endpoint group to project association.
:param endpoint_group_id: identity of endpoint to associate
:type endpoint_group_id: string
:param project_id: identity of project to associate
:type project_id: string
:raises keystone.exception.Conflict: If the endpoint group was already
added to the project.
:returns: None.'

@abc.abstractmethod
def add_endpoint_group_to_project(self, endpoint_group_id, project_id):

    raise exception.NotImplemented()
