Hi,
The said fields cannot be set via the Google Ads API, you may only be able to retrieve them. They should be generated once you setup conversion tracking. For more information, you may refer to this
guide.
Should you require further assistance on how to set this up, you may reach out to the
Google Ads Community Forum as they are better equipped to assist you regarding this matter. I hope this helps.
Thanks and regards,
Peter
Google Ads API Team

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