code: def yieldOutput(self):
          
          width = self.__width
          if width:
              num_cols = len(width)
              fmt = ['%%%ds' % -w for w in width]
              if width[-1] > 0:
                  fmt[-1] = '%s'
              fmt = self.__sep.join(fmt)
              for row in self.__cols:
                  row.extend( [''] * (num_cols - len(row)) )
                  yield fmt % tuple(row)
docs: Generate the text output for the table.
  
          @rtype:  generator of str
          @return: Text output.