code: def transform_cat_2(x):
      return "-".join(sorted(x.split("/")))
  
file_path: BigDL/python/friesian/example/multi_task/data_processing.py
imports: import os
  from argparse import ArgumentParser
  from bigdl.dllib.utils.log4Error import invalidInputError
  from bigdl.orca import init_orca_context, stop_orca_context
  from bigdl.friesian.feature import FeatureTable
label_desc: Use image node_id 2 for calling a global function with example usage: transform_cat_2(x) and returns: str