Sqlalchemy usermodel with password checking

gistfile1.py

class User(Base):
    __tablename__ = 'users'

    id = sa.Column(sa.Integer, primary_key=True)
    username = sa.Column(sa.Unicode(255),
                         unique=True,
                         nullable=False,
                         index=True)
    _password = sa.Column(sa.Unicode(255), nullable=False)
    last_logged = sa.Column(sa.DateTime, default=datetime.datetime.utcnow)

    def check_password(self, password):
        if len(password) > 4096:
            return False
        pass_hash = crypt(password, self._password)
        return self.password == pass_hash

    @property
    def password(self):
        return self._password

    @password.setter
    def password(self, value):
        if len(value) > 4096:
            raise ValueError("Password too long")
        salt = uuid.uuid4().hex
        pass_hash = crypt(value, salt, 400)
        self._password = pass_hash