---
title: Python-SDK - 5.3.0
slug: feature-experimentation/release-notes/python-sdk-5-3-0
docTags: 
createdAt: 2026-07-20T15:45:42.231Z
---

## What's Changed

[#whats-changed](docId\:OT25Lw_91_UG_H0ZUoWQH)

- \[FSSDK-11362] Fix CSRF security warning by @pvcraven in [https://github.com/optimizely/python-sdk/pull/448](https://github.com/optimizely/python-sdk/pull/448)
- \[FSSDK-11362] Import CSRFProtect from a better spot so prisma picks it up by @pvcraven in [https://github.com/optimizely/python-sdk/pull/450](https://github.com/optimizely/python-sdk/pull/450)
- \[FSSDK-11139] update: enable project config to track CMAB properties by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/451](https://github.com/optimizely/python-sdk/pull/451)
- \[FSSDK-11362] Try 3 to fix prisma scan issue with CSRF by @pvcraven in [https://github.com/optimizely/python-sdk/pull/452](https://github.com/optimizely/python-sdk/pull/452)
- \[FSSDK-11017] update: experiment\_id and variation\_id added to payloads by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/447](https://github.com/optimizely/python-sdk/pull/447)
- \[FSSDK-11157] update: add remove method in LRU Cache for CMAB service by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/454](https://github.com/optimizely/python-sdk/pull/454)
- \[FSSDK-11148] update: Implement CMAB Client by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/453](https://github.com/optimizely/python-sdk/pull/453)
- \[FSSDK-11166] update: implement CMAB service by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/455](https://github.com/optimizely/python-sdk/pull/455)
- \[FSSDK-11175] Update: Implement Decision Service methods to handle CMAB by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/457](https://github.com/optimizely/python-sdk/pull/457)
- \[FSSDK-11184] Update: Send CMAB uuid in impression events by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/458](https://github.com/optimizely/python-sdk/pull/458)
- \[FSSDK-11458] Python - Add SDK Multi-Region Support for Data Hosting by @esrakartalOpt in [https://github.com/optimizely/python-sdk/pull/459](https://github.com/optimizely/python-sdk/pull/459)
- \[FSSDK-11789] Maintenance: remove unused testapp folder from tests by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/461](https://github.com/optimizely/python-sdk/pull/461)
- \[FSSDK-11901] Fix concurrency bug in cmab service by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/462](https://github.com/optimizely/python-sdk/pull/462)
- \[FSSDK-11569]\[FSSDK-11570] Python: Holdout Project Config update by @esrakartalOpt in [https://github.com/optimizely/python-sdk/pull/464](https://github.com/optimizely/python-sdk/pull/464)
- \[FSSDK-11991] update: expose CMAB cache configuration options by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/463](https://github.com/optimizely/python-sdk/pull/463)
- \[FSSDK-12010] Expose cmab prediction endpoint in py sdk by @Mat001 in [https://github.com/optimizely/python-sdk/pull/466](https://github.com/optimizely/python-sdk/pull/466)
- \[FSSDK-11571] Python: Add holdout support and refactor decision logic in DefaultDecisionService by @esrakartalOpt in [https://github.com/optimizely/python-sdk/pull/467](https://github.com/optimizely/python-sdk/pull/467)
- \[FSSDK-11958] chore: Release v5.3.0 by @FarhanAnjum-opti in [https://github.com/optimizely/python-sdk/pull/468](https://github.com/optimizely/python-sdk/pull/468)

## New Contributors

[#new-contributors](docId\:OT25Lw_91_UG_H0ZUoWQH)

- @esrakartalOpt made their first contribution in [https://github.com/optimizely/python-sdk/pull/459](https://github.com/optimizely/python-sdk/pull/459)

**Full Changelog**: [https://github.com/optimizely/python-sdk/compare/5.2.0...5.3.0](https://github.com/optimizely/python-sdk/compare/5.2.0...5.3.0)

[https://github.com/optimizely/python-sdk/releases/tag/5.3.0](https://github.com/optimizely/python-sdk/releases/tag/5.3.0)