Returns the main dataframe's tail

        :param rows: number of rows to print, defaults to 5
        :param rows: int, optional
        :return: a pandas dataframe
        :rtype: pd.DataFrame

        :example: ``ds.tail()``

def tail(self, rows: int=5):
        """
        Returns the main dataframe's tail

        :param rows: number of rows to print, defaults to 5
        :param rows: int, optional
        :return: a pandas dataframe
        :rtype: pd.DataFrame

        :example: ``ds.tail()``
        """
        if self.df is None:
            self.warning("Dataframe is empty: no tail available")
        return self.df.tail(rows)