def select_regions(df, regions, col_name="denominazione_regione"):
    """
    Select rows by values in regions from column col_name
    :param df: pandas dataFrame
    :param regions: a list of values
    :param col_name: a string indicating the column
    :return: a new DataFrame with only the selected rows of df
    """
    return df[df[col_name].isin(regions)].reset_index()