def METHOD_NAME(cls, legit=None, legit_on_issn=None):
    def mock(*arg, **kwarg):
        if legit is not None:
            return legit
        if legit_on_issn is not None:
            article = arg[0]
            issns = article.bibjson().issns()
            for issn in issns:
                if issn in legit_on_issn:
                    return True
            return False
        return False
    return mock