AttributeError: 'NoneType' object has no attribute 'drivername'

[gowrisankar1998]

AttributeError
AttributeError: 'NoneType' object has no attribute 'drivername'

Traceback (most recent call last)
File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\sqlalchemy\util_collections.py", line 1010, in call
return self.registry[key]

During handling of the above exception, another exception occurred:

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask\app.py", line 2463, in call
return self.wsgi_app(environ, start_response)

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask\app.py",
line 2449, in wsgi_app
response = self.handle_exception(e)

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask\app.py", line 1866, in handle_exception
reraise(exc_type, exc_value, tb)

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask_compat.py", line 39, in reraise
raise value

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask\app.py", line 2446, in wsgi_app
response = self.full_dispatch_request()

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask\app.py", line 1951, in full_dispatch_request
rv = self.handle_user_exception(e)

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask\app.py", line 1820, in handle_user_exception
reraise(exc_type, exc_value, tb)

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask_compat.py", line 39, in reraise
raise value

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask\app.py", line 1949, in full_dispatch_request
rv = self.dispatch_request()

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask\app.py", line 1935, in dispatch_request
return self.view_functionsrule.endpoint

File "C:\Users\my pc\3D Objects\13-Deployment-Linode\flaskblog\main\routes.py", line 11, in home
posts = Post.query.order_by(Post.date_posted.desc()).paginate(page=page, per_page=5)

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask_sqlalchemy_init_.py", line 519, in get
return type.query_class(mapper, session=self.sa.session())

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\sqlalchemy\orm\scoping.py", line 78, in call
return self.registry()

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\sqlalchemy\util_collections.py", line 1012, in call
return self.registry.setdefault(key, self.createfunc())

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\sqlalchemy\orm\session.py", line 3225, in call
return self.class_(**local_kw)

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask_sqlalchemy_init_.py", line 138, in init
bind = options.pop('bind', None) or db.engine

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask_sqlalchemy_init_.py", line 937, in engine
return self.get_engine()

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask_sqlalchemy_init_.py", line 956, in get_engine
return connector.get_engine()

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask_sqlalchemy_init_.py", line 560, in get_engine
options = self.get_options(sa_url, echo)

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask_sqlalchemy_init_.py", line 575, in get_options
self._sa.apply_driver_hacks(self._app, sa_url, options)

File "C:\Users\my pc\AppData\Local\Programs\Python\Python38\Lib\site-packages\flask_sqlalchemy_init_.py", line 877, in apply_driver_hacks
if sa_url.drivername.startswith('mysql'):

AttributeError: 'NoneType' object has no attribute 'drivername'
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[gowrisankar1998]

I deleted this code from the routes.py and other problems arised in code after this .Then the page started running but when clicked on login and registration "KeyError: 'A secret key is required to use CSRF." is shown

File "C:\Users\my pc\3D Objects\13-Deployment-Linode\flaskblog\main\routes.py", line 11, in home
posts = Post.query.order_by(Post.date_posted.desc()).paginate(page=page, per_page=5)