def METHOD_NAME(self, s):
    if s is None:
        return None
    count = len(s.transitions)
    look = [] * count
    for alt in range(0, count):
        look[alt] = set()
        lookBusy = set()
        seeThruPreds = False # fail to get lookahead upon pred
        self._LOOK(s.transition(alt).target, None, PredictionContext.EMPTY, \
              look[alt], lookBusy, set(), seeThruPreds, False)
        # Wipe out lookahead for this alternative if we found nothing
        # or we had a predicate when we !seeThruPreds
        if len(look[alt])==0 or self.HIT_PRED in look[alt]:
            look[alt] = None
    return look