Certificate export with python suds in f5-bigip

Hello,

i'm trying to export certificates via a python soap client:

for c in cert_ids:
    test = client.factory.create('Common.StringSequence')
    test.item = [c]
    try :
              pem = client.service.certificate_export_to_pem('MANAGEMENT_MODE_DEFAULT', test)
              print('found : ', pem)
    except:
              print('could not find certificate with id : ', test)

However i'm only getting the default f5-bigip certificates (/Common/f5-irule, /Common/default ... ) and not the certificates that i have created.

Can someone please help me fix my python code ?

EDIT:

certs_ids = [ '/Common/default', '/Common/mycert', '/Common/mycert2' ]

Thank you in advance.