code: def K(self):
          
          K = np.eye(3, dtype=np.float64)
          K[0, 0] = self.focal[0]
          K[1, 1] = self.focal[1]
          K[0, 2] = self.resolution[0] / 2.0
          K[1, 2] = self.resolution[1] / 2.0
          return K
docs: Get the intrinsic matrix for the Camera object.
  
          Returns
          -----------
          K : (3, 3) float
            Intrinsic matrix for camera