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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 highlighted_fulltext(self):
 """Highlight the found terms in the fulltext."""

        terms = self.fields.get('fulltext', [])
        if not terms:
            return None
        arguments = {'id': self['id'],
                     'query': ' & '.join(terms),
                     }
        with db_connect() as db_connection:
            with db_connection.cursor() as cursor:
                cursor.execute(_read_sql_file('highlighted-fulltext'),
                               arguments)
                hl_fulltext = cursor.fetchone()[0]
        return hl_fulltext