def METHOD_NAME(bbhandler, pn, taskname, sig1=None, sig2=None):
    """ Find the most recent signature files for the specified PN/task """
    if not taskname.startswith('do_'):
        taskname = 'do_%s' % taskname
    if sig1 and sig2:
        sigfiles = find_siginfo(bbhandler, pn, taskname, [sig1, sig2])
        if len(sigfiles) == 0:
            logger.error('No sigdata files found matching %s %s matching either %s or %s' % (pn, taskname, sig1, sig2))
            sys.exit(1)
        elif not sig1 in sigfiles:
            logger.error('No sigdata files found matching %s %s with signature %s' % (pn, taskname, sig1))
            sys.exit(1)
        elif not sig2 in sigfiles:
            logger.error('No sigdata files found matching %s %s with signature %s' % (pn, taskname, sig2))
            sys.exit(1)
        latestfiles = [sigfiles[sig1], sigfiles[sig2]]
    else:
        filedates = find_siginfo(bbhandler, pn, taskname)
        latestfiles = sorted(filedates.keys(), key=lambda f: filedates[f])[-2:]
        if not latestfiles:
            logger.error('No sigdata files found matching %s %s' % (pn, taskname))
            sys.exit(1)
    return latestfiles