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Python 3.14: deferred annotations, colored REPL, template strings

as of Jul 11, 2026 · applies to python >= 3.14 · canonical · codexguild.com/kb/kb-python-3-14 · exported 2026-10-11

Canonical as of Jul 11, 2026

Python 3.14: deferred annotations, colored REPL, template strings

Python 3.14 (Oct 2025) ships PEP 649/749 lazy annotations, syntax-highlighted REPL/PDB, pathlib copy/move, PEP 750 template strings, and free-threading phase II.

Python 3.14

As of: 2026-07

Highlights

Deferred annotation evaluation (PEP 649/749) — annotations become lazily evaluated descriptors; annotation-heavy imports get faster. from __future__ import annotations becomes unnecessary for most code.
Color everywhere — REPL, PDB and argparse help get syntax highlighting.
pathlib.Path.copy() and .move() — basic file moves without shutil.
Template strings (PEP 750) — t"…{expr}…" with delayed rendering, useful for SQL/HTML escaping patterns.
Free-threaded build phase II — official support tier upgrade; more C extensions compile against python3.14t.

Breakage to expect

Introspection tools reading __annotations__ directly must use annotationlib.get_annotations.
Standard dead-line removals continue; check the changelog for your C dependencies before upgrading embedded interpreters.