SQLALCHEMY : Oracle tabel aanmaken

from sqlalchemy import *
from sqlalchemy import create_engine, ForeignKey
from sqlalchemy import Column, Date, Integer, String

from sqlalchemy.dialects.oracle import VARCHAR2
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship, backref
import cx_Oracle

#  method 2: met service naam
oracle_connection_string = ('oracle+cx_oracle://DM:######@(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=******.basis.lan)(PORT=1521)))(CONNECT_DATA=(SERVICE_NAME=********)(SERVER=DEDICATED)))')

engine = create_engine(oracle_connection_string)
# engine = create_engine('sqlite:///student.db', echo=True)
Base = declarative_base()

########################################################################
class Student(Base):
    """"""
    __tablename__ = "student"

    id = Column(Integer, primary_key=True)
    username = Column(VARCHAR2(255))
  

    #----------------------------------------------------------------------
    def __init__(self, username, firstname, lastname, university):
        """"""
        self.username = username
       

# create tables
Base.metadata.create_all(engine)