code: def get_device(device_id=None, use_chainerx=False):
      """Get device object
  
      Currently in Chainer, there are 3 officially-supported backends
      (numpy, cupy, and chainerx) and 2 devices (CPU and NVIDIA GPUs).
      Also, ChainerX has its own backend system, so there are 4 combinations
      (numpy, cupy, chainerx+native, chainerx+cuda). This utility function
      is a boilerplate to get device object in ChainerMN contexts.
      """
      if device_id is not None:
          if use_chainerx:
              device = "cuda:{}".format(device_id)
          else:
              device = "@cupy:{}".format(device_id)
      else:
          if use_chainerx:
              device = "native:0"
          else:
              device = "@numpy"
  
      return chainer.get_device(device)
  
label_desc: Use image node_id 1 for calling a global function with example usage: get_device(device_id, use_chainerx) and returns: chainer