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Sep 22, 2026 · Backend Development

Python 3.15: 7 Game-Changing Features Developers Need to Know

Python 3.15 introduces seven major features including lazy imports for faster startup, built-in frozendict for immutable mappings, sentinel objects to replace None checks, an upgraded JIT compiler delivering 8-13% speedups, clearer error messages with cross-language method suggestions, and a rollback of the incremental garbage collector due to memory overhead.