LangChain 1.0 Upgrade Migration (Python) Overview The first deploy after crashes on import with: Fix the import, restart, and the next error lands: LangChain 1.0 removed four entire public-API surfaces in one release: - Provider imports under / (pain code P38 ). - The family under ( P39 ). - and siblings under ( P40 ). - under ( P41 ). Anything that inspected also breaks because the tuple shape changed from to ( P42 ). This skill walks a reversible, phased migration: 1. A pre-flight grep audit. 2. A pinned package upgrade (including the 1.0 peer-pin against , P66 ). 3. Codemod patterns for th…