code: def null_auth() -> bsa.NullAuth:
      return bsa.NullAuth()
  
imports: from __future__ import annotations
  import pytest
  from types import ModuleType
  from tornado.web import RequestHandler
  from tests.support.util.api import verify_all
  from tests.support.util.filesystem import with_file_contents, with_file_contents_async
  import bokeh.server.auth_provider
label_desc: Use image node_id 1 for calling a global function with example usage: null_auth() and returns: bsa