langchain

5ac0d1f6 - partners[anthropic]: fix anthropic chat model message type lookup keys (#19034)

partners[anthropic]: fix anthropic chat model message type lookup keys (#19034) - **Description:** Fixing message formatting issue in ChatAnthropic model by adding dictionary keys for `AIMessageChunk `and `HumanMessageChunk` - **Issue:** #19025 - **Twitter handle:** @maximeperrin_ Co-authored-by: Maxime Perrin <mperrin@doing.fr> Co-authored-by: Erick Friis <erick@langchain.dev>