Provide WatsonX/BAM models as langchain.chat_models

[dove-young]

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Status

READY

Description

langchain.chat_models does not include WatsonX/BAM models
It is not able to run langchain via WatsonX/BAM models so far.

like
https://python.langchain.com/docs/use_cases/question_answering
and
https://python.langchain.com/docs/use_cases/question_answering/code_understanding

just for examples.

So it is not able to leverage langchain capacities with WatsonX/BAM models.

Impacted Areas in Library

• genai.extensions.langchain.watsonx
• genai.extensions.langchain.bam

Which issue(s) does this pull-request fix?

#215

Any special notes for your reviewer?

There are 2 classes in this PR

• Classes:
  • genai.extensions.langchain.watsonx provides a class WatsonX, act as a LLM to work with langchain.chat_models.
  • genai.extensions.langchain.bam provides a class BAM, act as a client of WatsonX to work with BAM API

Here you can find 2 examples implement langchain use cases using this PR

• Examples:
  • examples/user/langchain_rag_qa.py
    • https://python.langchain.com/docs/use_cases/question_answering
  • examples/user/langchain_rag_code.py
    • https://python.langchain.com/docs/use_cases/question_answering/code_understanding

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Checklist

• Automated tests exist
• Updated Package Requirements (if required, and with maintainers' approval)
• Local unit tests performed
• Documentation exists link
• Local pre-commit hooks performed
• Desired commit message set as PR title and description set above
• Link to relevant GitHub issue provided