code: def get_department(the_col: Union[str, f.Column]) -> f.Column:
      _the_col = (
          the_col if isinstance(the_col, f.Column) else f.col(the_col)
      )
      return f.element_at(f.split(_the_col, "_"), 1)
  
imports: import os
  import tempfile
  import unittest
  from typing import Dict, Optional, Set, Type, Union
  from pandas.testing import assert_frame_equal
  from pyspark.sql import DataFrame, types, functions
  from synapse.ml.cyber.feature import indexers
  from synapse.ml.cyber import DataFactory
  from synapse.ml.cyber.anomaly.collaborative_filtering import AccessAnomaly, AccessAnomalyModel, AccessAnomalyConfig, ConnectedComponents, ModelNormalizeTransformer, _UserResourceFeatureVectorMapping
  from synapsemltest.cyber.explain_tester import ExplainTester
  from synapsemltest.spark import *
label_desc: Use image node_id 3 for calling a global function with example usage: get_department(the_col) and returns: f