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## 1.28.3

**`(fix):`** The README's Environments example for a multi-URL SDK passes the environment constant through
the client's `environment:` keyword instead of `base_url:`. With more than one URL per
environment the constant is a hash of URLs, and `base_url:` expects a string, so the example
built a client that could not make a request. Single-URL SDKs keep `base_url:`.