@Override
    @SuppressWarnings("unchecked")
    public <T> T getTtlAttachment(@NonNull String key) {
        return (T) attachments.get(key);
    }
{@link TtlAttachments} delegate/implementation.

@author Jerry Lee (oldratlee at gmail dot com)
@see com.alibaba.ttl.TtlRunnable
@see com.alibaba.ttl.TtlCallable
@since 2.11.0
ttl2-compatible/src/main/java/com/alibaba/ttl/spi/TtlAttachmentsDelegate.java