public function addTags($id, array $tags, $identifyBy = 'email')
    {
        $request = new Request('subscribers');
        $request->setQuery(['identified_by' => $identifyBy]);
        $request->setIdParam($id);
        $request->addSubresource(['name' => 'tags']);
        $request->setParams(['tags' => $tags]);

        $response = $this->client->post($request);

        $this->assertSuccessResponse($response);

        return $response->getData();

    }