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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def render(self, rows):
 """ Join the HTML rows. """

        if not rows:
            return ''

        li_tags = mark_safe(u"\n".join(format_html(u'<li>{0}</li>', force_text(row)) for row in rows))
        if self.title:
            return format_html(u'<div class="toolbar-title">{0}</div>\n<ul>\n{1}\n</ul>', self.title, li_tags)
        else:
            return format_html(u'<ul>\n{0}\n</ul>', li_tags)