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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def process_frames_face(self, frames):
 """ Preprocess from frames using face detector """

        detector = dlib.get_frontal_face_detector()
        predictor = dlib.shape_predictor(self.face_predictor_path)
        mouth_frames = self.get_frames_mouth(detector, predictor, frames)
        self.face = np.array(frames)
        self.mouth = np.array(mouth_frames)
        if mouth_frames[0] is not None:
            self.set_data(mouth_frames)