def METHOD_NAME(self):
    os = self.create_overload_selector(kind='casts')
    all_types = set(t for sig, impl in os.versions for t in sig)
    # ensure there are no ambiguous cast overloads
    # note: using permutations to avoid testing cast to the same type
    for sig in permutations(all_types, r=2):
        try:
            os.find(sig)
        except NumbaNotImplementedError:
            pass   # ignore not implemented cast