Render the form and all sections to HTML

def render(self):
        """Render the form and all sections to HTML"""
        return Markup(env.get_template('form.html').render(form=self,
                                                           render_open_tag=True,
                                                           render_close_tag=True,
                                                           render_before=True,
                                                           render_sections=True,
                                                           render_after=True,
                                                           generate_csrf_token=None if self.disable_csrf else _csrf_generation_function))