Description

Fixes ImportError: /usr/local/lib/python3.12/site-packages/tensorflow_text/core/pybinds/libpybinds_library_common.so: undefined symbol: icudt77_dat when running multimodal SFT tests (e.g., test_qwen3_multimodal_sft.sh).

DAG Error Log

Root Cause

1. A recent requirement regeneration commit (bde759abd) automatically bumped tensorflow and tensorflow-text to >=2.21.0 in the post-train requirements.
2. Version 2.21.0 of tensorflow-text introduces a dependency on the ICU 77 library (icudt77_dat), which is currently missing from the base workload container environment.
3. (Dependency Generation) During local test regeneration, seed-env using extreme lowest resolution (--resolution=lowest) attempted to fetch markdown==2.6.8 (required by tensorboard). This ancient version fails to build on Python 3.12 due to the removal of the imp module.

Solution

1. Explicitly pinned tensorflow==2.20.0 and tensorflow-text==2.20.1 in src/dependencies/extra_deps/tpu_post_train_overrides.txt to rollback to the working versions.
2. Added markdown>=3.4.1 to the overrides to prevent the seed-env resolution failure on Python 3.12.
3. Regenerated the src/dependencies/requirements/generated_requirements/tpu-post-train-requirements.txt lockfile.

Tests

Gemma3-4b Multimodal SFT: https://cloudlogging.app.goo.gl/TgW1NRpZNEGPHMk27
Qwen3-vl-2b Multimodal SFT: https://cloudlogging.app.goo.gl/N61H2VC3UUPNMiK59

Checklist

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