Why In-App Dynamic Dependency Resolution Fails Under PEP 668 (And What It Taught Us About SQLAlchemy Implicit Flushes) When testing or building proof-of-concept (PoC) scripts for concurrency bugs—such as deadlock conditions triggered by SQLAlchemy's autoflush behavior—it is tempting to make reproduction scripts fully self-contained. A common developer impulse is to automate dependency checks right inside the entry point so that team members can run the script without manual setup. Howev...