code: def init(cls, conn_string=None):
          
          if conn_string:
              _update_meta(conn_string)
              # We initialize the engine within the models module because models'
              # schema can depend on which data types are supported by the engine
              Meta.Session = new_sessionmaker()
              Meta.engine = Meta.Session.kw["bind"]
              logger.info(
                  f"Connecting user:{Meta.DBUSER} "
                  f"to {Meta.DBHOST}:{Meta.DBPORT}/{Meta.DBNAME}"
              )
              Meta._init_db()
  
          if not Meta.log_path:
              init_logging()
  
          return cls
docs: Return the unique Meta class.