community: update perplexity documentation (#30450)
This pull request includes updates to the
`docs/docs/integrations/chat/perplexity.ipynb` file to enhance the
documentation for `ChatPerplexity`. The changes focus on demonstrating
the use of Perplexity-specific parameters and supporting structured
outputs for Tier 3+ users.
Enhancements to documentation:
* Added a new markdown cell explaining the use of Perplexity-specific
parameters through the `ChatPerplexity` class, including parameters like
`search_domain_filter`, `return_images`, `return_related_questions`, and
`search_recency_filter` using the `extra_body` parameter.
* Added a new code cell demonstrating how to invoke `ChatPerplexity`
with the `extra_body` parameter to filter search recency.
Support for structured outputs:
* Added a new markdown cell explaining that `ChatPerplexity` supports
structured outputs for Tier 3+ users.
* Added a new code cell demonstrating how to use `ChatPerplexity` with
structured outputs by defining a `BaseModel` class and invoking the chat
with structured output.[Copilot is generating a summary...]Thank you for
contributing to LangChain!
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Co-authored-by: Chester Curme <chester.curme@gmail.com>
