code: def init(cls, flask_or_import_name, directory=None, config=None):
          
          if isinstance(flask_or_import_name, Flask):
              app = flask_or_import_name
          else:
              app = Flask(flask_or_import_name)
  
          app.wsgi_app = ProxyFix(app.wsgi_app)
  
          if config:
              app.config.from_object(config)
  
          if directory:
              app.template_folder = directory + "/templates"
              app.static_folder = directory + "/static"
  
          cls._app = app
          cls.assets = Environment(cls._app)
  
          for _app in cls._bind:
              _app(cls._app)
  
          for subcls in cls.__subclasses__():
              subcls.register(cls._app)
  
          return cls._app
docs: Allow to register all subclasses of Pylot
          So we call it once initiating
          :param flask_or_import_name: Flask instance or import name -> __name__
          :param directory: The directory containing your project's Views, Templates and Static
          :param config: string of config object. ie: "app.config.Dev"