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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 _filter_exact(self, term, field_name, field_type, is_not):
 """ Returns a query that matches exactly the un-stemmed term with positional order. Assumes term is not a list. """

        if field_type == 'text' and field_name not in (DJANGO_CT,):
            term = '^ %s $' % term
            query = self._phrase_query(term.split(), field_name, field_type)
        else:
            query = self._term_query(term, field_name, field_type, stemmed=False)

        if is_not:
            return xapian.Query(xapian.Query.OP_AND_NOT, self._all_query(), query)
        else:
            return query