code: def proxy(name, default = None):
      
      proxymodule = _ProxyMetaClass(name, (_ProxyModule,), {'_default': default})
      proxymodule.__module__ = sys._getframe(1).f_globals.get('__name__')
      return proxymodule
docs: Create a proxy module. A proxy module has a default implementation, but can be redirected to other
      implementations with configurations. Other modules can depend on proxy modules.