alter session set CONTAINER with CX_Oracle

Now i use cx_oracle with python to execute oracle statements. I have oracle CDB and PDBs. I need to execute this statement from CDB to PDB (MYPDB)

ALTER SESSION SET CONTAINER=MYPDB;SELECT (SELECT instance_name FROM v$instance) as CDB_NAME, (SELECT SYS_CONTEXT('USERENV', 'CON_NAME') FROM dual) as PDB_NAME ,a.owner ,a.table_name ,a.column_name ,b.comments FROM dba_tab_columns a LEFT JOIN dba_col_comments b ON a.owner = b.owner AND a.table_name = b.table_name AND a.column_name = b.column_name WHERE a.OWNER LIKE 'USR_%'ORDER BY a.owner, a.table_name, a.column_name ASC

It works in sql developer but not in cx_oracle. My script is:

conn = cx_Oracle.connect(user=self.user, password=self.password, dsn=self.connection_string)cursor = conn.cursor()cursor.execute("""alter session set CONTAINER=PB24                    SELECT a.owner, a.table_name, b.comments FROM dba_tables a LEFT JOIN dba_tab_comments b ON a.owner = b.owner AND a.table_name = b.table_name WHERE a.OWNER LIKE 'USR_%' ORDER BY a.owner, a.table_name ASC;""")

and return ORA-00922: missing or invalid option

Python version: 3.10.14Oracle version: 18gcx_version: 8 latest