What file do I include to use the FaceRecognizer class in the iOS framework?

Hi, I'm trying to implement the Face Recognizer class using the instructions I found [here](http://docs.opencv.org/trunk/da/d60/tutorial_face_main.html) I noticed it includes a file called `opencv2/face.hpp` which seems to contain the `cv::face` namespace and the `BasicFaceRecognizer` class. The problem is that I cant seem to find the `face.hpp` file in the opencv iOS framework which I downloaded from http://opencv.org/releases.html (I'm using OpenCV 3.2) What file do I need to include in my project to use the face recognition API? Thank You