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+==========
+frozenlist
+==========
+
+.. image:: https://github.com/aio-libs/frozenlist/workflows/CI/badge.svg
+   :target: https://github.com/aio-libs/frozenlist/actions
+   :alt: GitHub status for master branch
+
+.. image:: https://codecov.io/gh/aio-libs/frozenlist/branch/master/graph/badge.svg
+   :target: https://codecov.io/gh/aio-libs/frozenlist
+   :alt: codecov.io status for master branch
+
+.. image:: https://badge.fury.io/py/frozenlist.svg
+   :target: https://pypi.org/project/frozenlist
+   :alt: Latest PyPI package version
+
+.. image:: https://readthedocs.org/projects/frozenlist/badge/?version=latest
+   :target: https://frozenlist.readthedocs.io/
+   :alt: Latest Read The Docs
+
+.. image:: https://img.shields.io/discourse/topics?server=https%3A%2F%2Faio-libs.discourse.group%2F
+   :target: https://aio-libs.discourse.group/
+   :alt: Discourse group for io-libs
+
+.. image:: https://badges.gitter.im/Join%20Chat.svg
+   :target: https://gitter.im/aio-libs/Lobby
+   :alt: Chat on Gitter
+
+Introduction
+============
+
+``frozenlist.FrozenList`` is a list-like structure which implements
+``collections.abc.MutableSequence``. The list is *mutable* until ``FrozenList.freeze``
+is called, after which list modifications raise ``RuntimeError``:
+
+
+>>> from frozenlist import FrozenList
+>>> fl = FrozenList([17, 42])
+>>> fl.append('spam')
+>>> fl.append('Vikings')
+>>> fl
+<FrozenList(frozen=False, [17, 42, 'spam', 'Vikings'])>
+>>> fl.freeze()
+>>> fl
+<FrozenList(frozen=True, [17, 42, 'spam', 'Vikings'])>
+>>> fl.frozen
+True
+>>> fl.append("Monty")
+Traceback (most recent call last):
+  File "<stdin>", line 1, in <module>
+  File "frozenlist/_frozenlist.pyx", line 97, in frozenlist._frozenlist.FrozenList.append
+    self._check_frozen()
+  File "frozenlist/_frozenlist.pyx", line 19, in frozenlist._frozenlist.FrozenList._check_frozen
+    raise RuntimeError("Cannot modify frozen list.")
+RuntimeError: Cannot modify frozen list.
+
+
+FrozenList is also hashable, but only when frozen. Otherwise it also throws a RuntimeError:
+
+
+>>> fl = FrozenList([17, 42, 'spam'])
+>>> hash(fl)
+Traceback (most recent call last):
+  File "<stdin>", line 1, in <module>
+  File "frozenlist/_frozenlist.pyx", line 111, in frozenlist._frozenlist.FrozenList.__hash__
+    raise RuntimeError("Cannot hash unfrozen list.")
+RuntimeError: Cannot hash unfrozen list.
+>>> fl.freeze()
+>>> hash(fl)
+3713081631934410656
+>>> dictionary = {fl: 'Vikings'} # frozen fl can be a dict key
+>>> dictionary
+{<FrozenList(frozen=True, [1, 2])>: 'Vikings'}
+
+
+Installation
+------------
+
+::
+
+   $ pip install frozenlist
+
+The library requires Python 3.6 or newer.
+
+
+Documentation
+=============
+
+https://frozenlist.readthedocs.io/
+
+Communication channels
+======================
+
+*aio-libs discourse group*: https://aio-libs.discourse.group
+
+Feel free to post your questions and ideas here.
+
+*gitter chat* https://gitter.im/aio-libs/Lobby
+
+Requirements
+============
+
+- Python >= 3.6
+
+License
+=======
+
+``frozenlist`` is offered under the Apache 2 license.
+
+Source code
+===========
+
+The project is hosted on GitHub_
+
+Please file an issue in the `bug tracker
+<https://github.com/aio-libs/frozenlist/issues>`_ if you have found a bug
+or have some suggestions to improve the library.
+
+.. _GitHub: https://github.com/aio-libs/frozenlist