---
id: frozenlist
version: "1.8.0"
license: Apache-2.0
license_treatment: permissive
maintenance: active
---

# frozenlist — A list-like structure which implements collections.abc.MutableSequence

License: permissive · Maintenance: active · Popularity: top 100 on PyPI

## Install

pip install frozenlist
uv add frozenlist
poetry add frozenlist

## Description

frozenlist
==========

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   :alt: codecov.io status for master branch

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   :target: https://pypi.org/project/frozenlist
   :alt: frozenlist @ PyPI

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   :target: https://frozenlist.aio-libs.org
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   :target:...

## AI interpretation — verify before relying

frozenlist provides a mutable list that can be frozen to prevent further modifications, raising RuntimeError on mutation attempts after freeze() is called, and supporting hashing only when frozen.

Verdict: frozenlist is a stable, actively maintained utility (top-100 PyPI tier, no known vulnerabilities) offering a simple pattern for transitioning lists from mutable to immutable with zero external dependencies and broad Python 3.9+ support including PyPy.

[View on SkillFed](https://skillfed.io/packages/frozenlist) · [View on PyPI](https://pypi.org/project/frozenlist/)