Flask-sqlalchemy check if data already exits in table before Inserting

I am trying to insert some values into table using flask sqllite methods but I am not sure how to make the statement equivalent to Insert into table if not exits , the below method adds the data but if already present I want to ignore it kindly guide on the same

 pl1 = mydb(employee_name='JOhn doe')
  db.session.add(pl1)
  db.commit()

>Solution :

Maybe this

pl1 = mydb(employee_name='JOhn doe')

if not db_session.query(mydb).filter_by(employee_name='JOhn doe').first():
    db_session.add(pl1)
    db_session.commit()

I usually use db or db_session. I don’t know if your db.session is a typo. In any case it should be easy to adjust the syntax.