SQLAlchemy не могу сменить провайдера для БД

class Configuration(object):
    DEBUG = True
    SQLALCHEMY_TRACK_MODIFICATIONS = False
    SQLALCHEMY_DATABASE_URI = "mysql+pymysql://root:1111@localhost/test1"

 
app = Flask(__name__)
app.config.from_object(Configuration)
 
db = SQLAlchemy(app)

from app import db
from datetime import datetime
import re
 
 
def slugify(s):
    pattern = r"[^\w+]"
    return re.sub(pattern, "-", s)
 
 
class Post(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(140))
    slug = db.Column(db.String(140), unique=True)
    body = db.Column(db.Text)
    created = db.Column(db.DateTime, default=datetime.now())
 
    def __init__(self, *args, **kwargs):
        super(Post, self).__init__(*args, **kwargs)
        self.generate_slug()
 
    def generate_slug(self):
        if self.title:
            self.slug = slugify(self.title)
 
    def __repr__(self):
        return "<Post id: {0}, title: {1}>".format(self.id, self.title)

>>> import models
E:\PYTHON\Flask\Two\venv\lib\site-packages\flask_sqlalchemy\__init__.py:813: UserWarning: Neither SQLALCHEMY_DATABASE_URI nor SQLALCHEMY_BINDS is set. Defaulting SQLALCHEMY_DATABASE_URI to "sqlite:///:memory:".
  'Neither SQLALCHEMY_DATABASE_URI nor SQLALCHEMY_BINDS is set. '
>>> from app import db
>>> db.create_all()
>>> from models import Post
>>> p = Post(title="123", body="sdfvdv")
>>> p
<Post id: None, title: 123>
>>> db.session.add(p)
>>> db.session.commit()
>>> Post.query.all()
[<Post id: 1, title: 123>]
>>>

>>> db.engine.name
'sqlite'

>>> db.engine
Engine(mysql+mysqlconnector://root:***@localhost:3306/test1?charset=utf8)
>>> db.metadata.tables.keys()
dict_keys(['post'])