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## 4.42.0

**`(feat):`** Add async support for OAuth token provider. The generated SDK now includes an AsyncOAuthTokenProvider
class that uses asyncio.Lock for async-safe token refresh, alongside the existing sync OAuthTokenProvider
that uses threading.Lock. The async client now uses the async token provider for proper async token management.

## 4.41.3

**`(fix):`** Fix multipart form data requests to omit None values instead of converting them to empty strings.
This prevents httpx from sending empty strings for optional parameters that should be absent.