def add_blank_row(self, label):
        """
        Add a blank row with only an index value to self.df.
        This is done inplace.
        """
        col_labels = self.df.columns
        blank_item = pd.Series({}, index=col_labels, name=label)
        # use .loc to add in place (append won't do that)
        self.df.loc[blank_item.name] = blank_item
        return self.df
Add a blank row with only an index value to self.df.
        This is done inplace.