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## 5.34.2

**`(fix):`** Accept an `async_token` callable on the async root client when OAuth client credentials are
configured with a token override. Previously only a synchronous `token` callable could be
supplied in token mode, so resolving the token blocked the event loop on every request. The
async client now exposes `async_token: Optional[Callable[[], Awaitable[str]]]`, adds a
constructor overload for it, and forwards it to `AsyncClientWrapper`.

**`(fix):`** When `async_token` is set on an async client, the synchronous `token` is no longer resolved
for async requests. `AsyncClientWrapper.async_get_headers()` now calls
`get_headers(include_token=False)` and uses only the awaited token, so a blocking `token`
callable never runs on the event loop.