langchain

0486404a - langchain_openai[patch]: Invoke callback prior to yielding token (#18269)

langchain_openai[patch]: Invoke callback prior to yielding token (#18269) ## PR title langchain_openai[patch]: Invoke callback prior to yielding token ## PR message Description: Invoke callback prior to yielding token in _stream and _astream methods for langchain_openai. Issue: https://github.com/langchain-ai/langchain/issues/16913 Dependencies: None Twitter handle: None