code: def test_parquet_parser_column_skip():
      # generate a big frame with all datatypes and save it to csv.  Load it back with different skipped_columns settings
      csv = h2o.import_file(
          path=pyunit_utils.locate(
              "smalldata/airlines/AirlinesTrain.csv.zip"
          )
      )
      parquetNoSkip = h2o.import_file(
          path=pyunit_utils.locate(
              "smalldata/parser/parquet/airlines-simple.snappy.parquet"
          )
      )
      pyunit_utils.compare_frames_local(
          csv, parquetNoSkip, prob=1
      )  # should be the same here.
  
      path = pyunit_utils.locate(
          "smalldata/parser/parquet/airlines-simple.snappy.parquet"
      )
      skip_all = list(range(csv.ncol))
      skip_even = list(range(0, csv.ncol, 2))
      skip_odd = list(range(1, csv.ncol, 2))
      skip_start_end = [0, csv.ncol - 1]
      skip_except_last = list(range(0, csv.ncol - 2))
      skip_except_first = list(range(1, csv.ncol))
      temp = list(range(0, csv.ncol))
      random.shuffle(temp)
      skip_random = []
      for index in range(0, csv.ncol // 2):
          skip_random.append(temp[index])
      skip_random.sort()
  
      try:
          loadFileSkipAll = h2o.upload_file(
              path, skipped_columns=skip_all
          )
          assert (
              False
          ), "Test should have thrown an exception due to all columns are skipped"  # should have failed here
      except:
          pass
  
      try:
          importFileSkipAll = h2o.import_file(
              path, skipped_columns=skip_all
          )
          assert (
              False
          ), "Test should have thrown an exception due to all columns are skipped"  # should have failed here
      except:
          pass
  
      # skip even columns
      pyunit_utils.checkCorrectSkips(csv, path, skip_even)
  
      # skip odd columns
      pyunit_utils.checkCorrectSkips(csv, path, skip_odd)
  
      # skip the very beginning and the very end.
      pyunit_utils.checkCorrectSkips(csv, path, skip_start_end)
  
      # skip all except the last column
      pyunit_utils.checkCorrectSkips(csv, path, skip_except_last)
  
      # skip all except the very first column
      pyunit_utils.checkCorrectSkips(csv, path, skip_except_first)
  
      # randomly skipped half the columns
      pyunit_utils.checkCorrectSkips(csv, path, skip_random)
  
imports: import sys
  import h2o
  from tests import pyunit_utils
  import random
label_desc: Use image node_id 1 for calling a global function with example usage: test_parquet_parser_column_skip() without return types