Use package metadata for pydeequ version

[Mirochill]

Issue #, if available:
Closes #239

Description of changes:

• derive pydeequ.__version__ from installed package metadata instead of a stale hardcoded string
• add a regression test that compares pydeequ.__version__ with importlib.metadata.version(pydeequ)

Validation:

• git diff --check HEAD~1..HEAD
• static review of pydeequ/__init__.py and tests/test_version.py
• Tests not run locally

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[github-actions]

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Generated by AI (model: us.anthropic.claude-opus-4-6-v1, prompt: 416310f3) — may not be fully accurate. Reply if this doesn't help.

[github-actions]

EDGE_CASE: importlib.metadata.version("pydeequ") will raise PackageNotFoundError if the package is not installed in the environment (e.g., running from source checkout without pip install -e .). This makes the module completely unimportable in that scenario, whereas the previous hardcoded string always worked. Consider wrapping in a try/except to fall back gracefully.

Line 17: __version__ = version("pydeequ") — importlib.metadata.version() raises importlib.metadata.PackageNotFoundError (a subclass of ModuleNotFoundError) when the distribution is not found. A developer cloning the repo and running python -c 'import pydeequ' without installing the package will get an unhandled exception at import time.

[github-actions]

DESIGN: The test is tautological — pydeequ.__version__ is defined as version("pydeequ") and the test asserts it equals version("pydeequ"). It can never fail unless the import itself fails. It doesn't guard against regressions (e.g., someone re-hardcoding the version). A more useful test would verify the version string matches a semver pattern or matches pyproject.toml.

In pydeequ/__init__.py line 17: __version__ = version("pydeequ"). In tests/test_version.py line 7-8: assert pydeequ.__version__ == version("pydeequ"). Both sides call the same function with the same argument, so the assertion is x == x.