def locations_map(locations_df):
    """Return a locations map:
    {
        'country': ['UnitedStates'],
        'county': [
            'Abbeville_SouthCarolina_UnitedStates',
            'Acadia_Louisiana_UnitedStates',
            ...
        ],
        'state': [
            'Alabama_UnitedStates',
            'Alaska_UnitedStates',
            ...
        ],
    }
    """
    return locations_df.groupby("locationType").id.apply(list).to_dict()