* were added by default.
     */
    fun clearHeaders() =
      apply {
        headers = Headers.Builder()
      }

    /**
     * Adds [header] as an HTTP header. For well-formed HTTP [header] should contain a name followed
     * by a colon and a value.
     */
    fun addHeader(header: String) =
      apply {
        headers.add(header)
      }

    /**

      }

      return false
    }

    /**
     * Attempt to parse a `Set-Cookie` HTTP header value [setCookie] as a cookie. Returns null if
     * [setCookie] is not a well-formed cookie.
     */
    @JvmStatic
    fun parse(
      url: HttpUrl,
      setCookie: String,
    ): Cookie? = parse(System.currentTimeMillis(), url, setCookie)

    internal fun parse(

    prepared to build a TLS API for Kotlin/Native.

    We'd prefer a multiplatform HTTP client API that's backed by OkHttp on Android and JVM, and
    other engines on other platforms. [Ktor] does this pretty well today!

 *  Breaking: Use `kotlin.time.Duration` in APIs like `OkHttpClient.Builder.callTimeout()`. This
    update also drops support for the `DurationUnit` functions introduced in earlier alpha releases
    of OkHttp 5.

    the timeouts manually.

 *  **OkHttp now rejects request headers that contain invalid characters.** This
    includes potential security problems (newline characters) as well as simple
    non-ASCII characters (including international characters and emoji).

 *  **Call canceling is more reliable.**  We had a bug where a socket being

      }

      // If this response shouldn't have been stored, it should never be used as a response source.
      // This check should be redundant as long as the persistence store is well-behaved and the
      // rules are constant.
      if (!isCacheable(cacheResponse, request)) {
        return CacheStrategy(request, null)
      }

      val requestCaching = request.cacheControl

 * or network should be done asynchronously.
 */
abstract class EventListener {
  /**
   * Invoked as soon as a call is enqueued or executed by a client. In case of thread or stream
   * limits, this call may be executed well before processing the request is able to begin.
   *
   * This will be invoked only once for a single [Call]. Retries of different routes or redirects

R8 / ProGuard
-------------

R8 and ProGuard are both code optimizers for `.class` files.

R8 is the [default optimizer][r8] in Android Studio 3.4 and newer. It works well with all
releases of OkHttp.

ProGuard was the previous default. We’re [tracking problems][proguard_problems] with interactions
between ProGuard, OkHttp 4.x, and Kotlin-originated `.class` files. Make sure you’re on the latest