Python 3.15: features that didn't make the headlines

Python 3.15 introduces several overlooked features beyond the headline-grabbing lazy imports and tachyon profiler. Key additions include TaskGroup.cancel() for simplified asyncio cancellation, improved ContextDecorator that now properly handles async functions and generators as decorators, and thread-safe iterators. These smaller features address common pain points in concurrent programming and decorator design that previously required workarounds.