Merge pull request #385 from openai/kwhinnery-openai-patch-1

Update README.md

Author: kwhinnery-openai

README.md

@@ -1,3 +1,7 @@
 # OpenAPI spec for the OpenAI API
 
 This repository contains an [OpenAPI](https://www.openapis.org/) specification for the [OpenAI API](https://platform.openai.com/docs/api-reference).
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+## Public mirror - do not send pull requests
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+This is a public mirror of the internal OpenAI REST API specification. Pull requests to this spec document will not be merged. In the future, we may enable contributions and corrections via contribution to the spec, but for now they cannot be accepted. Thank you!