[Fire162]

Issue #, if available

Fixes #6539

Description

get_base_python_image_uri previously accepted any string for py_version without validation. For Python versions without base images in ECR (such as 311 or 313), it returned image URIs that failed downstream during job creation when pulling from ECR.

Fix

• Added "py_versions": ["310", "38"] to versions["1.0"] in sagemaker-core/src/sagemaker/core/image_uri_config/sagemaker-base-python.json.
• Added validation in get_base_python_image_uri via _validate_py_version_and_set_if_needed, matching how framework image URIs validate python versions across the SDK.
• Updated docstring to document the ValueError raised on unsupported versions.
• Added unit test coverage in sagemaker-core/tests/unit/image_uris/test_base_python.py for unsupported python versions.

Testing done

• Ran pytest sagemaker-core/tests/unit/image_uris/test_base_python.py -> 7 passed.
• Verified valid versions (310, 38) resolve expected URIs across all regions.
• Verified invalid/unsupported versions (311, 312, 313, 39, invalid) raise ValueError: Unsupported Python version.

Merge Checklist

• I have read the CONTRIBUTING doc
• I used the commit message format described in CONTRIBUTING
• I have passed the region in to all S3 and STS clients that I've initialized as part of this change (N/A)
• I have updated any necessary documentation, including READMEs and API docs (if appropriate)

Tests

• I have added tests that prove my fix is effective or that my feature works (if appropriate)
• I have added unit and/or integration tests as appropriate to ensure backward compatibility of the changes

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