docs: public void putAttribute(String key, AttributeValue value) {
      // Not final because for performance reasons we want to override this in the implementation.
      // Also a default implementation is needed to not break the compatibility (users may extend this
      // for testing).
      Utils.checkNotNull(key, "key");
      Utils.checkNotNull(value, "value");
      putAttributes(Collections.singletonMap(key, value));
    }