def filter_valid_tournaments(df):
    """Filter for valid tournaments

    Notes:
        Excluding Tour championship for 2019 and 2020
        due to rule change in score totals.

    Args:
        df (pd.DataFrame) : espn tournaments

    Returns:
        valid_df (pd.Dataframe) : valid espn tournaments

    """
    valid_df = df[~df.winner_name.isnull()].copy()
    valid_df = valid_df[~((valid_df["tournament_id"] == 401056542) | (valid_df["tournament_id"] == 401155476))]

    return valid_df