Why does SQL command failed when executed using cx_oracle but works manually?

Question

I am working on oracle12C1 RAC setup, I am trying to migrate FILE wallet to HSM, currently my sqlnet.ora on both node is as follows:

Node1: ENCRYPTION_WALLET_LOCATION = ( SOURCE =(METHOD = HSM)(METHOD_DATA = (DIRECTORY = /etc/ORACLE/WALLET/ORCL)))
Node2: ENCRYPTION_WALLET_LOCATION = ( SOURCE =(METHOD = HSM)
                                        (METHOD_DATA =
                                       (DIRECTORY = /etc/ORACLE/WALLET/ORCL)))

I am trying to migrate wallet from FILE wallet to HSM wallet as follows using cx_Oracle

ADMINISTER KEY MANAGEMENT SET ENCRYPTION KEY IDENTIFIED BY "Ssl12345#" MIGRATE USING "ssl12345" with backup

and getting following error

ORA-28416: specify the correct keystore in the sqlnet.ora file

and If I execute it manually by invoking sqlplus on node1 it works smoothly.

SQL> ADMINISTER KEY MANAGEMENT SET ENCRYPTION KEY IDENTIFIED BY "Ssl12345#" MIGRATE USING "ssl12345" with backup;

keystore altered.

Can you please tell exactly whats the difference between these two execution?

My effort: I tried searching for this particular oracle error and got nothing more than

When migrating to HSM, the keystore specified in sqlnet.ora file should be HSM and similarly when migrating to wallet, the keystore specified in sqlnet.ora should be wallet. Check if the sqlnet.ora file configuration is correct and, if not, correct it.