'Retrieve the endpoint group associated with the id if exists.'

@controller.protected()
def get_endpoint_group_in_project(self, request, endpoint_group_id, project_id):

    self.resource_api.get_project(project_id)
    self.catalog_api.get_endpoint_group(endpoint_group_id)
    ref = self.catalog_api.get_endpoint_group_in_project(endpoint_group_id, project_id)
    return ProjectEndpointGroupV3Controller.wrap_member(request.context_dict, ref)
