def format_id_list(id_data_dict: dict) -> list:
    """ Helper function to create an ID list from an ID data dictionary.

    Args:
        id_data_dict (dict): Dictionary containing full IDs data.

    Returns:
        list: containing IDs only.
    """
    id_list = []

    for id_data in id_data_dict:
        # The API might return ID, Id or id as key, so converting dict keys to be lowercase.
        data = {k.lower(): v for k, v in id_data.items()}
        id_list.append(data.get('id', None))

    # Remove None objects from ID list, if exists.
    id_list = [id for id in id_list if id]
    return id_list