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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, template=None, additional=None):
 """ Render single model to its html representation. You may set template path in render function argument, or model's variable named 'template_path', or get default name: $app_label$/models/$model_name$.html Settings: * MODEL_RENDER_DEFAULT_EXTENSION set default template extension. Usable if you use jinja or others. :param template: custom template_path :return: rendered model html string """

        template_path = template or self.get_template_path()

        template_vars = {'model': self}
        if additional:
            template_vars.update(additional)

        rendered = render_to_string(template_path, template_vars)
        return mark_safe(rendered)