sqlite - Flask, SQLAlchemy: How to make column autoincrement -

i'm defining model this:

class user(usermixin, db.model):     __tablename__ = 'users'     id = db.column(db.integer, primary_key=true)     first = db.column(db.string(64))     last = db.column(db.string(64))     dob = db.column(db.date)     street_addr1 = db.column(db.string(64))     street_addr2 = db.column(db.string(64))     city = db.column(db.string(64))     state = db.column(db.string(2))     zip = db.column(db.string(9))     gender = db.column(db.enum('m', 'f'))     home_box = db.column(db.string(32))     username = db.column(db.string(64), unique=true, index=true)     password_hash = db.column(db.string(128))      @property     def password(self):         raise attributeerror('password not readable attribute')      @password.setter     def password(self, password):         self.password_hash = generate_password_hash(password)      def verify_password(self, password):         return check_password_hash(self.password_hash, password)     def __repr__(self):         return '<user %r>' % self.username  @login_manager.user_loader def load_user(user_id):     return user.query.get(int(user_id)) 

views.py:

@main.route('/', methods=['get', 'post']) def index():     form = registrationform()     if form.validate_on_submit():          user = user()         user.username = form.username.data         user.first = form.first_name.data         user.last = form.last_name.data         user.city = form.city.data         user.dob = form.dob.data         user.gender = form.gender.data         user.home_box = form.home_box.data         user.state = form.state.data         user.street_addr1 = form.street_addr1.data         user.street_addr2 = form.street_addr2.data         user.zip = form.zip.data         user.password = form.password.data         db.session.add(user)         db.session.commit 

right now, inserts failing because id not set:

sqlalchemy.exc.integrityerror: (integrityerror) constraint failed 'insert users  (first, last, dob, street_addr1, street_addr2, city, state, zip, gender, home_box, username, password_hash) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)' ('nate', 'reed', '1980-11-11', '', '', '', '', '', 'male', '', 'natereed', 'pbkdf2:sha1:1000$n8jhxedu$24a7724ae9edda81a73e6b92d23aa576ad8284aa') 

how make id autoincrement? understanding has done @ table (not column) level. how do in code above?

i figured out problem was trying insert value gender not valid. it's enum values 'm' or 'f'.

it nice if form generated model, eliminate potential error. pointers on doing flask?