Add a series to this data set entitled *name* and having the data
        points specified by *values*, an iterable of numeric values.
        *number_format* specifies how the series values will be displayed,
        and may be a string, e.g. '#,##0' corresponding to an Excel number
        format.

def add_series(self, name, values=(), number_format=None):
        """
        Add a series to this data set entitled *name* and having the data
        points specified by *values*, an iterable of numeric values.
        *number_format* specifies how the series values will be displayed,
        and may be a string, e.g. '#,##0' corresponding to an Excel number
        format.
        """
        series_data = CategorySeriesData(self, name, number_format)
        self.append(series_data)
        for value in values:
            series_data.add_data_point(value)
        return series_data