__init__ should pass login_manager instance to init_app?

[SleeplessAnnoyedNerd]

I think it is necessary to pass the login_manager to init_app in __init__ otherwise a new login_manager instance will be created in init_app. Which causes @login_required to return 401 instead of redirecting to Google. (Since context processor is assigned to the wrong login_manager instance.)

def __init__(self, app=None, login_manager=None):
    if login_manager:
        self.login_manager = login_manager
    else:
        self.login_manager = LoginManager()

    if app:
        self._app = app
        self.init_app(app, login_manager=self.login_manager)  # <=  pass current login_manager instance

I stumbled onto this as I tried following snippet from the documentation:

from flask_login import LoginManager
login_manager = LoginManager()
login_manager.init_app(app)
googlelogin = GoogleLogin(app, login_manager)