@Override
  public HttpResponse send(HttpRequest httpRequest) throws IOException {
    return send(httpRequest, null);
  }
@Test
  public void send_default_userAgent() throws IOException, InterruptedException {
    String responseBody = "test response";
    mockWebServer.enqueue(
        new MockResponse()
            .setResponseCode(HttpStatus.OK.code())
            .setHeader(CONTENT_TYPE, MediaType.PLAIN_TEXT_UTF_8.toString())
            .setBody(responseBody));
    mockWebServer.start();

    HttpUrl baseUrl = mockWebServer.url("/");
    httpClient.send(get(baseUrl.toString()).withEmptyHeaders().build());

    assertThat(mockWebServer.takeRequest().getHeader(USER_AGENT))
        .isEqualTo(HttpClient.TSUNAMI_USER_AGENT);
  }