Llama2 support for BedrockChat

[shafkevi]

Amazon recently announced support for Meta's Llama2 13B parameter model in the Amazon Bedrock service. This is not yet supported in langchain, and being a new model provider there is no payload mapper either.

[shafkevi]

I am working on this now 👍

[dosubot]

🤖

Hello @shafkevi,

I'm Dosu, your friendly bot here to assist you with bugs, answer your queries, and guide you on your journey to becoming a contributor to langchainjs. While we're waiting for a human maintainer to join us, I'm here to ensure you get the help you need. Looking forward to assisting you.

It seems like you've got this under control, if you want help or have specific questions, let me know what I can do for you!