code: def hdfs_basic():
      hdfs_name_node = pyunit_utils.hadoop_namenode()
      hdfs_iris_file = "/datasets/runit/iris_wheader.csv"
      hdfs_iris_dir = "/datasets/runit/iris_test_train"
  
      print("Testing single file importHDFS")
      url = "hdfs://{0}{1}".format(hdfs_name_node, hdfs_iris_file)
      iris_h2o = h2o.import_file(url)
      n = iris_h2o.nrow
      print("rows: {0}".format(n))
      assert (
          n == 150
      ), "Wrong number of rows. Got {0}. Should have got {1}".format(
          n, 150
      )
      assert isinstance(
          iris_h2o, h2o.H2OFrame
      ), "Wrong type. Expected H2OFrame, but got {0}".format(
          type(iris_h2o)
      )
      print("Import worked")
  
      print("Testing directory importHDFS")
      urls = [
          "hdfs://{0}{1}/iris_test.csv".format(
              hdfs_name_node, hdfs_iris_dir
          ),
          "hdfs://{0}{1}/iris_train.csv".format(
              hdfs_name_node, hdfs_iris_dir
          ),
      ]
      iris_dir_h2o = h2o.import_file(urls)
      iris_dir_h2o.head()
      iris_dir_h2o.tail()
      n = iris_dir_h2o.nrow
      print("rows: {0}".format(n))
      assert (
          n == 150
      ), "Wrong number of rows. Got {0}. Should have got {1}".format(
          n, 150
      )
      assert isinstance(
          iris_dir_h2o, h2o.H2OFrame
      ), "Wrong type. Expected H2OFrame, but got {0}".format(
          type(iris_dir_h2o)
      )
      print("Import worked")
  
imports: import sys
  import os
  from tests import pyunit_utils
  import h2o
label_desc: Use image node_id 1 for calling a global function with example usage: hdfs_basic() without return types