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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_contains(self, term, field_name, field_type, is_not):
 """ Splits the sentence in terms and join them with OR, using stemmed and un-stemmed. Assumes term is not a list. """

        if field_type == 'text':
            term_list = term.split()
        else:
            term_list = [term]

        query = self._or_query(term_list, field_name, field_type)
        if is_not:
            return xapian.Query(xapian.Query.OP_AND_NOT, self._all_query(), query)
        else:
            return query