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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 get_point_cloud(self, pair):
 """Get 3D point cloud from image pair."""

        disparity = self.block_matcher.get_disparity(pair)
        points = self.block_matcher.get_3d(disparity,
                                           self.calibration.disp_to_depth_mat)
        colors = cv2.cvtColor(pair[0], cv2.COLOR_BGR2RGB)
        return PointCloud(points, colors)