def _aggregate_player_attributes(player_df, columns):
    """Compute the mean for all the players for the given columns

    Parameters
    ----------
    player_df: pd.DataFrame
        The DataFrame containing the statistics of all the players
    columns: list
        The columns on which to calculate the mean

    Returns
    -------
    player_df_with_stats: pd.DataFrame
        The original DataFrame with also the aggregate stats
    """
    return player_df[columns].mean(axis=1, skipna=True)