code: def difflag1():
      # Make random pandas frame with 1,000,000 rows ranging from 0-100
      df = pd.DataFrame(
          np.random.randint(0, 100, size=(1000000, 1)),
          columns=list("A"),
      )
      # Take diff of pandas frame
      df_diff = df.diff()
      # Make into h2o frame for comparison later
      df_diff_h2o = h2o.H2OFrame(df_diff)
  
      # Convert pandas dataframe to H2OFrame
      fr = h2o.H2OFrame(df)
      # Take diff of H2O frame
      fr_diff = fr.difflag1()
  
      # Get diff of pandas diff and h2o's diff
      diff = abs(
          df_diff_h2o[1 : df_diff_h2o.nrow, :]
          - fr_diff[1 : fr_diff.nrow, :]
      )
  
      # Assert that max of diff is less than 1e-10
      assert diff.max() < 1e-10, "expected equal differencing"
  
imports: import sys
  import h2o
  from tests import pyunit_utils
  import pandas
  import numpy
label_desc: Use image node_id 1 for calling a global function with example usage: difflag1() without return types