def render(self, data, div_id="chart", head=""):
        """Render the data in HTML template."""
        if not self.is_valid_name(div_id):
            raise ValueError(
                "Name {} is invalid. Only letters, numbers, '_', and '-' are permitted ".format(
                    div_id))

        return Template(head + self.template).render(
            div_id=div_id.replace(" ", "_"),
            data=json.dumps(
                data, indent=4).replace("'", "\\'").replace('"', "'"))