code: def register(viewer, order=1):
      try:
          if issubclass(viewer, Viewer):
              viewer = viewer()
      except TypeError:
          pass  # raised if viewer wasn't a class
      if order > 0:
          _viewers.append(viewer)
      elif order < 0:
          _viewers.insert(0, viewer)
  
file_path: catboost/contrib/python/Pillow/py2/PIL/ImageShow.py
imports: from __future__ import print_function
  import os
  import subprocess
  import sys
  import tempfile
  from PIL import Image
label_desc: Use image node_id 1 for calling a global function with example usage: register(viewer, order) without return types