docs: def check_seq_exists(self, seq, amount_ntermwildcards):
          """Look up sequence in sqlite DB. Returns True or False if it
          exists (or not). When looking up a reversed DB with
          ntermwildcards: we reverse the sequence of the pep and add
          a LIKE and %-suffix to the query.
          """
          cursor = self.get_cursor()
          if amount_ntermwildcards > 0:
              seq = seq[::-1]
              sqlseq = '{}{}'.format(seq, '%')
              # FIXME non-parametrized string binding because if ? binding is
              # used the INDEX is not used when looking up, apparently because
              # the query cant be optimized when using LIKE and binding.
              sql = ('select seqs from known_searchspace where seqs LIKE '
                     '"{}"'.format(sqlseq))
              for match in cursor.execute(sql):
                  if match[0][:-amount_ntermwildcards] in seq:
                      return True
              return False
          else:
              sql = ('select exists(select seqs from known_searchspace '
                     'where seqs=? limit 1)')
              return cursor.execute(sql, (seq, )).fetchone()[0] == 1