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- Adds support for Sift Science API Version 205, including new [`$create_content`](https://siftscience.com/developers/docs/curl/events-api/reserved-events/create-content) and [`$update_content`](https://siftscience.com/developers/docs/curl/events-api/reserved-events/update-content) formats
- V205 APIs are now called -- **this is an incompatible change**
- Use `version = '204'` when constructing the Client to call the previous API version
- Adds support for content decisions to [Decisions API](https://siftscience.com/developers/docs/curl/decisions-api)
INCOMPATIBLE CHANGES INTRODUCED IN API V205:
- `$create_content` and `$update_content` have significantly changed, and the old format will be rejected
- `$send_message` and `$submit_review` events are no longer valid
- V205 improves server-side event data validation. In V204 and earlier, server-side validation accepted some events that did not conform to the published APIs in our [developer documentation](https://siftscience.com/developers/docs/curl/events-api). V205 does not modify existing event APIs other than those mentioned above, but may reject invalid event data that were previously accepted. **Please test your integration on V205 in sandbox before using in production.**