code: def pubdev_1431():
      hadoop_namenode_is_accessible = (
          pyunit_utils.hadoop_namenode_is_accessible()
      )
  
      if hadoop_namenode_is_accessible:
          hdfs_name_node = pyunit_utils.hadoop_namenode()
          airlines_billion_file = "/datasets/airlinesbillion.csv"
          url = "hdfs://{0}{1}".format(
              hdfs_name_node, airlines_billion_file
          )
          airlines_billion = h2o.import_file(url)
          airlines_billion[30] = airlines_billion[30].asfactor()
          gbm = h2o.gbm(
              x=airlines_billion[0:30],
              y=airlines_billion[30],
              ntrees=1,
              distribution="bernoulli",
              max_depth=1,
          )
          predictions = gbm.predict(airlines_billion)
          csv = os.path.join(os.getcwd(), "delete.csv")
          h2o.download_csv(predictions, csv)
          os.remove(csv)
      else:
          raise EnvironmentError
  
imports: import sys
  import h2o
  from tests import pyunit_utils
  import os
label_desc: Use image node_id 1 for calling a global function with example usage: pubdev_1431() without return types