def set_reviewers(refs, reviewers, username, server, ssh_port):
    """ Set reviewers using gerrit set-reviewers command

    :param refs: A list of references to ``patchsets``, can be SHA1s or Change-Ids
    :param reviewers: A list of Gerrit reviewers, username or group name,
                      no e-mails
    """
    cmd = ["ssh", "-p", str(ssh_port),
    "%s@%s" % (username, server),
    "gerrit", "set-reviewers"]
    cmd.extend(refs)
    for reviewer in reviewers:
        cmd.append("--add %s" + reviewer)
    qisys.command.call(cmd, quiet=True)
dataset/ETHPy150Open aldebaran/qibuild/python/qisrc/review.py/set_reviewers/operator `%` -> `+`