code: def load_camera(
      camera_path, scale_factor=1.0, scene_center=None, scene_scale=None
  ) -> cam.Camera:
      """Loads camera and rays defined by the center pixels of a camera.
  
      Args:
        camera_path: a path to a camera file.
        scale_factor: a factor to scale the camera image by.
        scene_center: the center of the scene where the camera will be centered to.
        scene_scale: the scale of the scene by which the camera will also be scaled
          by.
  
      Returns:
        A Camera instance.
      """
      if camera_path.suffix == ".json":
          camera = cam.Camera.from_json(camera_path)
      else:
          raise ValueError("File must have extension .pb or .json.")
  
      if scale_factor != 1.0:
          camera = camera.scale(scale_factor)
  
      if scene_center is not None:
          camera.position = camera.position - scene_center
      if scene_scale is not None:
          camera.position = camera.position * scene_scale
  
      return camera
  
imports: import abc
  import functools
  import itertools
  from typing import Any, Iterable, Optional, Sequence, Union
  from absl import logging
  from flax import jax_utils
  import jax
  import numpy
  import tensorflow
  from nerfies import camera
  from nerfies import gpath
  from nerfies import image_utils
  from nerfies import tf_camera
  from nerfies import utils
  from tensorflow.python.data.util import nest
label_desc: Use image node_id 2 for calling a global function with example usage: load_camera(camera_path, scale_factor, scene_center, scene_scale) and returns: camera