code: def test_DateFormat(self) -> None:
      assert tuple(bce.DateFormat) == (
          "ATOM",
          "W3C",
          "RFC-3339",
          "ISO-8601",
          "COOKIE",
          "RFC-822",
          "RFC-850",
          "RFC-1036",
          "RFC-1123",
          "RFC-2822",
          "RSS",
          "TIMESTAMP",
      )
  
imports: from __future__ import annotations
  import pytest
  from bokeh.colors import named
  from bokeh.palettes import __palettes__
  from tests.support.util.api import verify_all
  import bokeh.core.enums
label_desc: Use image node_id 7 for calling the Test_bce obj's underlying member method code with example usage: obj.test_DateFormat() without return types