'Make a new aside definition and usage ids, indicating an :class:`.XBlockAside` of type `aside_type`
commenting on an :class:`.XBlock` usage `usage_id`
Returns:
(aside_definition_id, aside_usage_id)'

def create_aside(self, definition_id, usage_id, aside_type):

    def_key = AsideDefinitionKeyV2(definition_id, aside_type)
    usage_key = AsideUsageKeyV2(usage_id, aside_type)
    return (def_key, usage_key)
