code: def test_rename_slugify_columns(self):
      strings = ["Test kož", "test 2", "test 2"]
  
      table = Table(self.rows, self.column_names, self.column_types)
      table2 = table.rename(strings, slug_columns=True)
      table3 = table.rename(strings, slug_columns=True, separator=".")
  
      self.assertColumnNames(table, ["one", "two", "three"])
      self.assertColumnNames(table2, ["test_koz", "test_2", "test_2_2"])
      self.assertColumnNames(table3, ["test.koz", "test.2", "test.2.2"])
  
file_path: agate/tests/test_table/test_rename.py
imports: import warnings
  from agate import Table
  from agate.data_types import Number, Text
  from agate.testcase import AgateTestCase
label_desc: Use image node_id 7 for calling the TestRename obj's underlying member method code with example usage: obj.test_rename_slugify_columns() without return types