code: def id_generator(
      size=6, chars=string.ascii_uppercase + string.digits
  ):
      return "".join(random.choice(chars) for _ in range(size))
  
file_path: h2o-3/h2o-py/tests/testdir_misc/pyunit_export_parquet_multi.py
imports: from builtins import range
  import sys
  import h2o
  from tests import pyunit_utils
  import string
  import os
  import glob
  import random
  from pandas.util.testing import assert_frame_equal
label_desc: Use image node_id 3 for calling a global function with example usage: id_generator(size, chars) and returns: str