def __init__(self, refname, **kwargs):
self.refname = refname<EOL>self.cat = kwargs.setdefault("<STR_LIT>", self.cat)<EOL>self.failsafe = kwargs.setdefault("<STR_LIT>", self.failsafe)<EOL>self.fuzzer = GramFuzzer.instance()<EOL>
Create a new ``Ref`` instance

        :param str refname: The name of the rule to reference
        :param str cat: The name of the category the rule is defined in