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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 _frames_and_index_map(self, skip_registration=False):
 """Retrieve a new frame from the Kinect and return a ColorImage, DepthImage, IrImage, and a map from depth pixels to color pixel indices. Parameters skip_registration : bool If True, the registration step is skipped. Returns ------- :obj:`tuple` of :obj:`ColorImage`, :obj:`DepthImage`, :obj:`IrImage`, :obj:`numpy.ndarray` The ColorImage, DepthImage, and IrImage of the current frame, and an ndarray that maps pixels of the depth image to the index of the corresponding pixel in the color image. Raises ------ RuntimeError If the Kinect stream is not running. """

        if not self._running:
            raise RuntimeError('Kinect2 device %s not runnning. Cannot read frames' %(self._device_num))

        # read frames
        frames = self._listener.waitForNewFrame()
        unregistered_color = frames['color']
        distorted_depth = frames['depth']
        ir = frames['ir']

        # apply color to depth registration
        color_frame = self._color_frame
        color = unregistered_color
        depth = distorted_depth
        color_depth_map = np.zeros([depth.height, depth.width]).astype(np.int32).ravel()
        if not skip_registration and self._registration_mode == Kinect2RegistrationMode.COLOR_TO_DEPTH:
            color_frame = self._ir_frame
            depth = lf2.Frame(depth.width, depth.height, 4, lf2.FrameType.Depth)
            color = lf2.Frame(depth.width, depth.height, 4, lf2.FrameType.Color)
            self._registration.apply(unregistered_color, distorted_depth, depth, color, color_depth_map=color_depth_map)

        # convert to array (copy needed to prevent reference of deleted data
        color_arr = copy.copy(color.asarray())
        color_arr[:,:,[0,2]] = color_arr[:,:,[2,0]] # convert BGR to RGB
        color_arr[:,:,0] = np.fliplr(color_arr[:,:,0])
        color_arr[:,:,1] = np.fliplr(color_arr[:,:,1])
        color_arr[:,:,2] = np.fliplr(color_arr[:,:,2])
        color_arr[:,:,3] = np.fliplr(color_arr[:,:,3])
        depth_arr = np.fliplr(copy.copy(depth.asarray()))
        ir_arr = np.fliplr(copy.copy(ir.asarray()))

        # convert meters
        if self._depth_mode == Kinect2DepthMode.METERS:
            depth_arr = depth_arr * MM_TO_METERS

        # Release and return
        self._listener.release(frames)
        return (ColorImage(color_arr[:,:,:3], color_frame),
                DepthImage(depth_arr, self._ir_frame),
                IrImage(ir_arr.astype(np.uint16), self._ir_frame),
                color_depth_map)