How to set bid strategy to just "Maximize conversion value"?

[patreeceeo]

I'm trying to use the google ads python library to create a campaign with a "maximize conversion value" bidding strategy using version 25.1.0 of this library. In the Ads web interface, I have a campaign I created manually with such a bidding strategy. The closest I've come to that with python is a campaign that the web UI says has a "Maximize conversion value (Target ROAS)" bidding strategy that was achieved with the following line in my script:

campaign.maximize_conversion_value.target_roas = 1.0

My confusion lies in how to use the Campaign class in the Python code. There doesn't seem to be a way to express "I just want maximize conversion value without specifying a target ROAS," which is what I'm after.

You might think the following line would do it.

campaign.bidding_strategy_type = BiddingStrategyTypeEnum.BiddingStrategyType.MAXIMIZE_CONVERSION_VALUE

But that resulted in the following error.

Error with message "The required field was not present.".
                On field: operations
                On field: create
                On field: campaign_bidding_strategy

But no matter what I set the campaign's campaign_bidding_strategy to, I get

AttributeError: Unknown field for Campaign: campaign_bidding_strategy