.sslSocketFactory(certificates.sslSocketFactory(), certificates.trustManager)
        .build()
  }

  fun run() {
    showUrl("https://squareup.com/robots.txt")
    showUrl("https://publicobject.com/helloworld.txt")
  }

  private fun showUrl(url: String) {
    val request = Builder().url(url).build()
    client.newCall(request)
      .execute()
      .use { response ->