code: def test_case_insensitive(self):
      cf.register_option("KanBAN", 1, "doc")
  
      assert "doc" in cf.describe_option("kanbaN", _print_desc=False)
      assert cf.get_option("kanBaN") == 1
      cf.set_option("KanBan", 2)
      assert cf.get_option("kAnBaN") == 2
  
      # gets of non-existent keys fail
      msg = r"No such keys\(s\): 'no_such_option'"
      with pytest.raises(OptionError, match=msg):
          cf.get_option("no_such_option")
      cf.deprecate_option("KanBan")
  
      assert cf._is_deprecated("kAnBaN")
  
imports: import pytest
  from pandas._config import config
  from pandas._config.config import OptionError
  import pandas
  import pandas._testing
label_desc: Use image node_id 6 for calling the TestConfig obj's underlying member method code with example usage: obj.test_case_insensitive() without return types