even for a single call.

    Interceptors that rewrite or replace the request body may now inadvertently interfere with
    duplex request bodies. Such interceptors should check `RequestBody.isDuplex()` and avoid
    accessing the request body when it is.

    Duplex calls require HTTP/2. If HTTP/1 is established instead the duplex call will fail. The
    most common use of duplex calls is [gRPC][grpc_http2].

   * accomplished through the returned multimap.
   *
   * <p>It is imperative that the user manually synchronize on the returned multimap when accessing
   * any of its collection views:
   *
   * {@snippet :
   * Multimap<K, V> multimap = Multimaps.synchronizedMultimap(
   *     HashMultimap.<K, V>create());
   * ...

   * accomplished through the returned multimap.
   *
   * <p>It is imperative that the user manually synchronize on the returned multimap when accessing
   * any of its collection views:
   *
   * {@snippet :
   * Multimap<K, V> multimap = Multimaps.synchronizedMultimap(
   *     HashMultimap.<K, V>create());
   * ...

 * java.util.Objects#requireNonNull(Object)}. Instead, use whichever of {@link
 * #checkNotNull(Object)} or {@link Verify#verifyNotNull(Object)} is appropriate to the situation.
 * (The same goes for the message-accepting overloads.)
 *
 * <h3>Only {@code %s} is supported</h3>
 *
 * <p>{@code Preconditions} uses {@link Strings#lenientFormat} to format error message template