Update Anthropic Client

[krrishdholakia]

Anthropic changed their python sdk - making this code line outdated.

https://github.com/DachengLi1/LongChat/blob/a824bda25c0082e60973c35c79b0f35d69c6be2d/longeval/utils.py#L307

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Would love to know if this might help - https://github.com/BerriAI/litellm

~Simple I/O library, that standardizes all the llm api calls to the OpenAI call

from litellm import completion

## set ENV variables
# ENV variables can be set in .env file, too. Example in .env.example
os.environ["OPENAI_API_KEY"] = "openai key"
os.environ["ANTHROPIC_API_KEY"] = "anthropic key"

messages = [{ "content": "Hello, how are you?","role": "user"}]

# openai call
response = completion(model="gpt-3.5-turbo", messages=messages)

# anthropic call
response = completion("claude-v-2", messages)

[krrishdholakia]

cc: @AnzeXie @DachengLi1

[AnzeXie]

Thanks for the heads up. We'll update the outdated codes.