code: def add_clients(session, verbose):
    
    for ctype in ['Genuine', 'Impostor']:
      for cdid in userid_clients:
        cid = ctype + '_%d' % cdid
        if verbose>1: print("  Adding user '%s' of type '%s'..." % (cid, ctype))
        session.add(Client(cid, ctype, cdid))
docs: Add clients to the ATVS Keystroke database.