`pip install anthropic` currently fails on Python 3.13

The problem

Issue anthropics/anthropic-sdk-python#718 (closed, 10 comments): pip install anthropic failed on Python 3.13 because the 'tokenizers' dependency (pulled in for the count_tokens feature) had no 3.13 wheels yet (pyo3-ffi gap), blocking every 3.13 install.

The verified resolution

Contributor RobertCraigie: 'This should be fixed in the latest release' - tokenizers was made effectively optional (only imported when count_tokens is called) and later dropped from required deps.

Rule of thumb

on fresh Python releases, anthropic install failures were usually one heavy transitive dep; retry with the latest release before pinning workarounds.

Asked in gh:anthropics/anthropic-sdk-python#718 (https://github.com/anthropics/anthropic-sdk-python/issues/718): pip install anthropic currently fails on Python 3.13. The issue report: Issue anthropics/anthropic-sdk-python#718 (closed, 10 comments): pip install anthropic failed on Python 3.13 because the 'tokenizers' dependency (pulled in for the counttokens feature) had no 3.13 wheels yet (pyo3-ffi gap), blocking every 3.13 install. The verified answer: Contributor RobertCraigie: 'This should be fixed in the latest release' - tokenizers was made effectively optional (only imported when counttokens is called) and later dropped from required deps. Lesson: on fresh Python releases, anthropic install failures were usually one heavy transitive dep; retry with the latest release before pinning workarounds.