code: public PersistedFace addFaceFromStream(String faceListId, byte[] image, AddFaceFromStreamOptionalParameter addFaceFromStreamOptionalParameter) {
          return addFaceFromStreamWithServiceResponseAsync(faceListId, image, addFaceFromStreamOptionalParameter).toBlocking().single().body();
      }
docs: Add a face to a face list. The input face is specified as an image with a targetFace rectangle. It returns a persistedFaceId representing the added face, and persistedFaceId will not expire.
  
  @param faceListId Id referencing a particular face list.
  @param image An image stream.
  @param addFaceFromStreamOptionalParameter the object representing the optional parameters to be set before calling this API
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws APIErrorException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent
  @return the PersistedFace object if successful.