import cx_Oracle
connection_string = "{user}/{password}@{server}:{port}/{sid}".format(
    user=config.DB_USER,
    password=config.DB_PASSWORD,
    server=config.DB_HOST,
    port=config.DB_PORT,
    sid=config.DB_SID)
db_conn = cx_Oracle.connect(connection_string)

cursor = db_conn.cursor()