class User(Base, BaseMixIn):

    __tablename__ = 'users'
    id = Column(BigInteger, primary_key=True, autoincrement=True)
    username = Column(String(30), nullable=False, unique=True)
    first_name = Column(String(length=100), nullable=False)
    last_name = Column(String(length=100), nullable=False)
    email = Column(String(100), nullable=False, unique=True)
    password = Column(String(256), nullable=False)
    logged_on =  Column(
        TIMESTAMP(timezone=False),
        default=func.now(),
        server_default=func.now(),
        nullable=False
        )
    registered_on = Column(
        TIMESTAMP(timezone=False),
        default=sql.func.now(),
        server_default=func.now(),
        nullable=False
        )