code: def colname_rename():
      print("Uploading iris data...")
  
      f1 = h2o.upload_file(
          pyunit_utils.locate("smalldata/iris/iris.csv")
      )
      f2 = copy.copy(f1)
  
      t1 = f1.rename(
          columns={
              "C2": "C1",
              "C1": "C2",
              "C3": "X3",
              "F0": "X0",
              "C3": "Y3",
          }
      )
      e1 = ["C2", "C1", "Y3", "C4", "C5"]
      assert (
          t1.names == e1
      ), "Expected the same column names but got {0} and {1}".format(
          t1.names, e1
      )
  
      t2 = f2.rename(
          columns={0: "X1", 2: "X3", -1: "X2", 20: "X20", 2: "Y3"}
      )
      e2 = ["X1", "C2", "Y3", "C4", "X2"]
      assert (
          t2.names == e2
      ), "Expected the same column names but got {0} and {1}".format(
          t2.names, e2
      )
  
imports: import sys
  import copy
  import h2o
  from tests import pyunit_utils
label_desc: Use image node_id 1 for calling a global function with example usage: colname_rename() without return types