def METHOD_NAME(key, action_data, action):
    if key not in action_data:
        action_data[key] = {
            "pretranslations_chrf_scores": list(),
            "pretranslations_approved": set(),
            "pretranslations_rejected": set(),
            "pretranslations_new": set(),
        }
    data = action_data[key]
    translation = action["translation"]
    if action["action_type"] == "translation:created":
        data["pretranslations_new"].add(translation)
    elif action["action_type"] == "translation:approved":
        data["pretranslations_approved"].add(translation)
        # Translation has been approved, no need to claculate the chrF++ score
        data["pretranslations_chrf_scores"].append(100)
    elif action["action_type"] == "translation:rejected":
        data["pretranslations_rejected"].add(translation)
        score = get_chrf_score(action)
        if score:
            data["pretranslations_chrf_scores"].append(score)