@Nullable
    @Contract(value = "null -> null; !null -> !null", pure = true)
    public static <T> TtlCallable<T> get(@Nullable Callable<T> callable) {
        return get(callable, false, false);
    }
Factory method, wrap input {@link Callable} to {@link TtlCallable}.
<p>
This method is idempotent.

@param callable input {@link Callable}
@return Wrapped {@link Callable}
ttl2-compatible/src/main/java/com/alibaba/ttl/TtlCallable.java