IP list items adding issue

I’m writing a program that can modify account IP List items via the Cloudflare API, I found instructions for this at https:///#rules-lists-create-list-items, but there isn’t an example of a request given here, I I don’t know what request body should be used to create an IP record, I tried {“ip”: “1.1.1.1”}, but the response was {
“code”: 10026,
“message”: “filters.api.invalid_json”
}, can anyone give me an example please? Thanks.