Django Nonl启动时出错：TypeError:\uuuu init\uuuuuu（）为DatabaseFeatures恰好接受2个参数（给定1个）

我刚从django Unrel 1fbce9199a32升级到496955a68561，现在在尝试运行应用程序时出现以下错误：

Traceback (most recent call last):
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 3211, in _HandleRequest
    self._Dispatch(dispatcher, self.rfile, outfile, env_dict)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 3154, in _Dispatch
    base_env_dict=env_dict)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 527, in Dispatch
    base_env_dict=base_env_dict)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 2404, in Dispatch
    self._module_dict)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 2314, in ExecuteCGI
    reset_modules = exec_script(handler_path, cgi_path, hook)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 2212, in ExecuteOrImportScript
    script_module.main()
  File "/Users/mike/Projects/xxx/xxx/common-apps/djangoappengine/main/main.py", line 45, in real_main
    util.run_wsgi_app(application)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/ext/webapp/util.py", line 97, in run_wsgi_app
    run_bare_wsgi_app(add_wsgi_middleware(application))
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/ext/webapp/util.py", line 115, in run_bare_wsgi_app
    result = application(env, _start_response)
  File "/Users/mike/Projects/xxx/xxx/common-apps/django/core/handlers/wsgi.py", line 265, in __call__
    response = self.get_response(request)
  File "/Users/mike/Projects/xxx/xxx/common-apps/django/core/handlers/base.py", line 160, in get_response
    response = self.handle_uncaught_exception(request, resolver, sys.exc_info())
  File "/Users/mike/Projects/xxx/xxx/common-apps/django/core/handlers/base.py", line 194, in handle_uncaught_exception
    return debug.technical_500_response(request, *exc_info)
  File "/Users/mike/Projects/xxx/xxx/common-apps/django/views/debug.py", line 58, in technical_500_response
    html = reporter.get_traceback_html()
  File "/Users/mike/Projects/xxx/xxx/common-apps/django/views/debug.py", line 109, in get_traceback_html
    frames = self.get_traceback_frames()
  File "/Users/mike/Projects/xxx/xxx/common-apps/django/views/debug.py", line 228, in get_traceback_frames
    pre_context_lineno, pre_context, context_line, post_context = self._get_lines_from_file(filename, lineno, 7, loader, module_name)
  File "/Users/mike/Projects/xxx/xxx/common-apps/django/views/debug.py", line 180, in _get_lines_from_file
    source = loader.get_source(module_name)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1289, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1954, in get_source
    full_path, search_path, submodule = self.GetModuleInfo(fullname)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1289, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1918, in GetModuleInfo
    submodule, search_path = self.GetParentSearchPath(fullname)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1289, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1897, in GetParentSearchPath
    parent_package = self.GetParentPackage(fullname)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1289, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1873, in GetParentPackage
    if self.find_module(fullname) is None:
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1289, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1603, in find_module
    search_path)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1289, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1841, in FindAndLoadModule
    description)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1289, in Decorate
    return func(self, *args, **kwargs)
  File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/tools/dev_appserver.py", line 1792, in LoadModuleRestricted
    description)
  File "/Users/mike/Projects/xxx/xxx/common-apps/django/db/__init__.py", line 77, in <module>
    connection = connections[DEFAULT_DB_ALIAS]
  File "/Users/mike/Projects/xxx/xxx/common-apps/django/db/utils.py", line 92, in __getitem__
    conn = backend.DatabaseWrapper(db, alias)
  File "/Users/mike/Projects/xxx/xxx/common-apps/djangoappengine/db/base.py", line 118, in __init__
    self.features = DatabaseFeatures()
TypeError: __init__() takes exactly 2 arguments (1 given)

回溯（最近一次呼叫最后一次）：
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第3211行，位于HandlerRequest中
自我调度（调度员、自我文件、输出文件、环境指令）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第3154行，在
基本（环境（dict=环境（dict））
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第527行，在调度中
base_env_dict=base_env_dict）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第2404行，在调度中
自我保护（模块）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第2314行，在ExecuteCGI中
重置模块=执行脚本（处理程序路径、cgi路径、钩子）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第2212行，在ExecuteOrImportScript中
脚本_module.main（）
文件“/Users/mike/Projects/xxx/xxx/common apps/djangappengine/main/main.py”，第45行，以real\u main格式
util.run_wsgi_应用程序（应用程序）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/ext/webapp/util.py”，第97行，在run\u wsgi\u app中
运行应用程序（添加中间件（应用程序））
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/ext/webapp/util.py”，第115行，在run\u bare\u wsgi\u应用程序中
结果=应用程序（环境、启动和响应）
文件“/Users/mike/Projects/xxx/xxx/common apps/django/core/handlers/wsgi.py”，第265行，在调用中__
响应=自我获取响应（请求）
文件“/Users/mike/Projects/xxx/xxx/common apps/django/core/handlers/base.py”，第160行，在get_响应中
response=self.handle\u uncaught\u异常（请求、解析器、sys.exc\u info（））
文件“/Users/mike/Projects/xxx/xxx/common apps/django/core/handlers/base.py”，第194行，在handle\u uncaught\u异常中
返回调试技术响应（请求，*exc信息）
文件“/Users/mike/Projects/xxx/xxx/common apps/django/views/debug.py”，第58行，技术响应
html=reporter.get\u traceback\u html（）
文件“/Users/mike/Projects/xxx/xxx/common apps/django/views/debug.py”，第109行，在get\u traceback\u html中
frames=self.get\u traceback\u frames（）
文件“/Users/mike/Projects/xxx/xxx/common apps/django/views/debug.py”，第228行，在get\u traceback\u框架中
pre\u context\u line否，pre\u context，context\u line，post\u context=self.\u从\u文件（文件名，行号，7，加载程序，模块名称）获取\u line\u
文件“/Users/mike/Projects/xxx/xxx/common apps/django/views/debug.py”，第180行，从文件获取行
source=loader.get\u source（模块名称）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第1289行
返回函数（self、*args、**kwargs）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第1954行，在get\u source中
完整路径，搜索路径，子模块=self.GetModuleInfo（全名）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第1289行
返回函数（self、*args、**kwargs）
GetModuleInfo中的文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第1918行
子模块，search_path=self.GetParentSearchPath（全名）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第1289行
返回函数（self、*args、**kwargs）
GetParentSearchPath中的文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第1897行
parent\u package=self.GetParentPackage（全名）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第1289行
返回函数（self、*args、**kwargs）
GetParentPackage中的文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第1873行
如果self.find_模块（全名）为None：
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine default.bundle/Contents/Resources/google\u appengine/google/appengine/tools/dev\u appserver.py”，第1289行
返回函数（self、*args、**kwargs）
文件“/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengi