def keep_lazy(*resultclasses):
    if not resultclasses:
        raise TypeError("You must pass at least one argument to keep_lazy().")

    def decorator(func):
        lazy_func = lazy(func, *resultclasses)

        @wraps(func)
        def wrapper(*args, **kwargs):
            for arg in list(args) + list(six.itervalues(kwargs)):
                if isinstance(arg, Promise):
                    break
            else:
                return func(*args, **kwargs)
            return lazy_func(*args, **kwargs)
        return wrapper
    return decorator
Find linear prediction filter using a Cholesky decomposition.
dataset/ETHPy150Open django/django/django/utils/functional.py/keep_lazy--crossover with--dataset/ETHPy150Open jjhelmus/nmrglue/nmrglue/process/proc_lp.py/find_lpc_cholesky