[FEATURE] Integrate Python Atheris Fuzzer

**Is your feature request related to a problem? Please describe. **
Project should enable Atheris Fuzzer - https://github.com/google/atheris

The issue names no files, tests, or entry points. Start by reviewing the repository's Python dependency and test setup, then read Atheris's integration requirements; done should mean the project can run the fuzzer in a documented, repeatable way.

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