I have an error "E sqlalchemy.exc.NoForeignKeysError: Can't find any foreign key relationships between 'user_test' and 'payments_test'

I am using flask-sqlalchemy. I am getting an error "E sqlalchemy.exc.NoForeignKeysError: Can't find any foreign key relationships between 'user_test' and 'payments_test'." My error I assume is caused by not having the right name for the FK column or the relationship.

If I were to change the table in the UserTest table to __tablename__= user_test and the __PaymentsTest__= payments_tests table how would that change the relationship column and the FK column?

Also I didn't include all the columns in the tables and I don't want to use a join because the tables were working outside of pytest.

The only difference is that the Pytest tables have Test added to the class and since this the second database specifically for pytest I included the bind_key.

class UserTest(UserMixin, db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    paymentstest = db.relationship('PaymentsTest', backref='UserTest', lazy=True) 
    bind_key = "testing_app_db"

def __repr__(self):
    return '<UserTest %r>' % self.username

class PaymentsTest(db.Model):
    '''
    One to many relationship
    This is the Many relationship. 
    '''
    id = db.Column(db.Integer, primary_key=True)
    item_name = db.Column(db.String(80))
    usertest_id = db.Column(db.Integer, db.ForeignKey('user_test.id'))
    bind_key = "testing_app_db"

    
    def __repr__(self):
        return '<PaymentsTest %r>' % self.item_name

`

Here is the full error.

https://hastebin.com/share/qucocologo.swift

source https://stackoverflow.com/questions/76244611/i-have-an-error-e-sqlalchemy-exc-noforeignkeyserror-cant-find-any-foreign-key