code: def _wrap_lines(self, line_source, point_size):
          
          text, remainder = self._break_line(line_source, point_size)
          lines = [text]
          if remainder:
              lines.extend(self._wrap_lines(remainder, point_size))
          return lines
docs: Return a sequence of str values representing the text in
          *line_source* wrapped within this fitter when rendered at
          *point_size*.