docs: def prune_by_ngram_size(self, minimum=None, maximum=None):
          """Removes results rows whose n-gram size is outside the
          range specified by `minimum` and `maximum`.
  
          :param minimum: minimum n-gram size
          :type minimum: `int`
          :param maximum: maximum n-gram size
          :type maximum: `int`
  
          """
          self._logger.info('Pruning results by n-gram size')
          if minimum:
              self._matches = self._matches[
                  self._matches[constants.SIZE_FIELDNAME] >= minimum]
          if maximum:
              self._matches = self._matches[
                  self._matches[constants.SIZE_FIELDNAME] <= maximum]