def _map_participants(participant_data):
    """Map participant IDs to names."""
    participants = {}
    for participant_wrapper in participant_data:
        participant = participant_wrapper['participant']
        if len(participant['group_player_ids']) == 1:
            pid = participant['group_player_ids'][0]
            participants[pid] = participant['name']
        pid = participant['id']
        participants[pid] = participant['name']
    return participants
