(-python) E:\Source\python>mkdocs serve
INFO     -  Building documentation...
Traceback (most recent call last):
  File "d:\program files\python3\lib\runpy.py", line 197, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "d:\program files\python3\lib\runpy.py", line 87, in _run_code
    exec(code, run_globals)
  File "E:\Source\python\Scripts\mkdocs.exe\__main__.py", line 7, in <module>
  File "e:\source\python\lib\site-packages\click\core.py", line 1137, in __call__
    return self.main(*args, **kwargs)
  File "e:\source\python\lib\site-packages\click\core.py", line 1062, in main
    rv = self.invoke(ctx)
  File "e:\source\python\lib\site-packages\click\core.py", line 1668, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "e:\source\python\lib\site-packages\click\core.py", line 1404, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "e:\source\python\lib\site-packages\click\core.py", line 763, in invoke
    return __callback(*args, **kwargs)
  File "e:\source\python\lib\site-packages\mkdocs\__main__.py", line 173, in serve_command
    serve.serve(dev_addr=dev_addr, livereload=livereload, **kwargs)
  File "e:\source\python\lib\site-packages\mkdocs\commands\serve.py", line 54, in serve
    config = builder()
  File "e:\source\python\lib\site-packages\mkdocs\commands\serve.py", line 49, in builder
    build(config, live_server=live_server, dirty=dirty)
  File "e:\source\python\lib\site-packages\mkdocs\commands\build.py", line 249, in build
    config = config['plugins'].run_event('config', config)
  File "e:\source\python\lib\site-packages\mkdocs\plugins.py", line 94, in run_event
    result = method(item, **kwargs)
  File "e:\source\python\lib\site-packages\mkdocs\contrib\search\__init__.py", line 56, in on_config
    self.config['lang'] = validate(config['theme']['locale'].language)
  File "e:\source\python\lib\site-packages\mkdocs\contrib\search\__init__.py", line 27, in run_validati
on
    raise config_options.ValidationError(
mkdocs.config.base.ValidationError: "zh" is not a supported language code.