support the new batch api

[yingzhuivy]

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Is your feature request related to a problem? Please describe.
OpenAI launched batch API: https://community.openai.com/t/batchapi-is-now-available/718416
could be very useful and it would be good if the library supports it
https://platform.openai.com/docs/api-reference/batch/create

Describe the solution you'd like
support of the batch api

Describe alternatives you've considered
n/a

Additional context
n/a

[ricboer0]

I too think this is very much needed and extremely useful!!!