'Highlighted the lines specified in the `hl_lines` option by
post-processing the token stream coming from `_format_lines`.'

def _highlight_lines(self, tokensource):

    hls = self.hl_lines
    for (i, (t, value)) in enumerate(tokensource):
        if (t != 1):
            (yield (t, value))
        if ((i + 1) in hls):
            if self.noclasses:
                style = ''
                if (self.style.highlight_color is not None):
                    style = ('    style="background-color:    %s"' % (self.style.highlight_color,))
                (yield (1, ('<span%s>%s</span>' % (style, value))))
            else:
                (yield (1, ('<span    class="hll">%s</span>' % value)))
        else:
            (yield (1, value))
