docs: def get_protein_group_content(pgmap, master):
      """For each master protein, we generate the protein group proteins
      complete with sequences, psm_ids and scores. Master proteins are included
      in this group.
  
      Returns a list of [protein, master, pep_hits, psm_hits, protein_score],
      which is ready to enter the DB table.
      """
      # first item (0) is only a placeholder so the lookup.INDEX things get the
      # correct number. Would be nice with a solution, but the INDEXes were
      # originally made for mzidtsv protein group adding.
      pg_content = [[0, master, protein, len(peptides), len([psm for pgpsms in
                                                             peptides.values()
                                                             for psm in pgpsms]),
                     sum([psm[1] for pgpsms in peptides.values()
                          for psm in pgpsms]),  # score
                     next(iter(next(iter(peptides.values()))))[3],  # coverage
                     next(iter(next(iter(peptides.values()))))[2],  # evid level
                     ]
                    for protein, peptides in pgmap.items()]
      return pg_content