code: def improper_property(root_path, device):
      read = fn.readers.webdataset(paths=[root_path], ext=["jpg"])
      return fn.get_property(read, key=["this key doesn't exist"])
  
imports: from nvidia.dali import pipeline_def
  import os
  import numpy
  from nvidia.dali import fn
  from test_utils import get_dali_extra_path
  from nose_utils import raises
  import tempfile
label_desc: Use image node_id 15 for calling a global function with example usage: improper_property(root_path, device) and returns: fn