Custom Scripts with pre-selected DeviceRole

[pulsar2022]

Hi, I like to write a custom Script where I can add one or more devices (PC,Printers) to Netbox. The user must type in the PC names and the MAC-Addr. And set the DeviceRole, and here is the Problem, that here is a big dropdown List with many of DeviceRoles. Here i like to have a pre-selected DeviceRole "Workstation".

I had test different things:
device_role = ObjectVar(model=DeviceRole, query_params={'device_id': 25})
and
device_role = ObjectVar(model=DeviceRole, query_params={'device_role': 'Workstation'})

Is there a default pre-selection possible similiar to DeviceStatusChoices? here it works how I need it for DeviceRole:

Active is pre-selected
status = ChoiceVar(DeviceStatusChoices, default=DeviceStatusChoices.STATUS_ACTIVE)

How I can make pre-selection for DeviceRole?
Thank You for any help