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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_gte(self, term, field_name, field_type, is_not):
 """ Private method that returns a xapian.Query that searches for any term that is greater than `term` in a specified `field`. """

        vrp = XHValueRangeProcessor(self.backend)
        pos, begin, end = vrp('%s:%s' % (field_name, _term_to_xapian_value(term, field_type)), '*')
        if is_not:
            return xapian.Query(xapian.Query.OP_AND_NOT,
                                self._all_query(),
                                xapian.Query(xapian.Query.OP_VALUE_RANGE, pos, begin, end)
                                )
        return xapian.Query(xapian.Query.OP_VALUE_RANGE, pos, begin, end)