code: def get_acs_for_protein_seq(self, seq):
          
          md5 = seq_md5(seq)
          return [r['ac'] for r in self._fetchall(self._queries['acs_for_protein_md5'], [md5])
                  ] + ['MD5_' + md5]
docs: returns a list of protein accessions for a given sequence.  The
          list is guaranteed to contain at least one element with the
          MD5-based accession (MD5_01234abc...def56789) at the end of the
          list.