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+:mod:`gzip` -- gzip compression & decompression
+===============================================
+
+.. module:: gzip
+   :synopsis: gzip compression & decompression
+
+|see_cpython_module| :mod:`python:gzip`.
+
+This module allows compression and decompression of binary data with the
+`DEFLATE algorithm <https://en.wikipedia.org/wiki/DEFLATE>`_ used by the gzip
+file format.
+
+.. note:: Prefer to use :class:`deflate.DeflateIO` instead of the functions in this
+   module as it provides a streaming interface to compression and decompression
+   which is convenient and more memory efficient when working with reading or
+   writing compressed data to a file, socket, or stream.
+
+**Availability:**
+
+* This module is **not present by default** in official MicroPython firmware
+  releases as it duplicates functionality available in the :mod:`deflate
+  <deflate>` module.
+
+* A copy of this module can be installed (or frozen)
+  from :term:`micropython-lib` (`source <https://github.com/micropython/micropython-lib/blob/master/python-stdlib/gzip/gzip.py>`_).
+  See :ref:`packages` for more information. This documentation describes that module.
+
+* Compression support will only be available if compression support is enabled
+  in the built-in :mod:`deflate <deflate>` module.
+
+Functions
+---------
+
+.. function:: open(filename, mode, /)
+
+   Wrapper around built-in :func:`open` returning a GzipFile instance.
+
+.. function:: decompress(data, /)
+
+   Decompresses *data* into a bytes object.
+
+.. function:: compress(data, /)
+
+   Compresses *data* into a bytes object.
+
+Classes
+-------
+
+.. class:: GzipFile(*, fileobj, mode)
+
+   This class can be used to wrap a *fileobj* which is any
+   :term:`stream-like <stream>` object such as a file, socket, or stream
+   (including :class:`io.BytesIO`). It is itself a stream and implements the
+   standard read/readinto/write/close methods.
+
+   When the *mode* argument is ``"rb"``, reads from the GzipFile instance will
+   decompress the data in the underlying stream and return decompressed data.
+
+   If compression support is enabled then the *mode* argument can be set to
+   ``"wb"``, and writes to the GzipFile instance will be compressed and written
+   to the underlying stream.
+
+   By default the GzipFile class will read and write data using the gzip file
+   format, including a header and footer with checksum and a window size of 512
+   bytes.
+
+   The **file**, **compresslevel**, and **mtime** arguments are not
+   supported. **fileobj** and **mode** must always be specified as keyword
+   arguments.
+
+Examples
+--------
+
+A typical use case for :class:`gzip.GzipFile` is to read or write a compressed
+file from storage:
+
+.. code:: python
+
+   import gzip
+
+   # Reading:
+   with open("data.gz", "rb") as f:
+       with gzip.GzipFile(fileobj=f, mode="rb") as g:
+           # Use g.read(), g.readinto(), etc.
+
+    # Same, but using gzip.open:
+   with gzip.open("data.gz", "rb") as f:
+        # Use f.read(), f.readinto(), etc.
+
+   # Writing:
+   with open("data.gz", "wb") as f:
+       with gzip.GzipFile(fileobj=f, mode="wb") as g:
+           # Use g.write(...) etc
+
+   # Same, but using gzip.open:
+   with gzip.open("data.gz", "wb") as f:
+       # Use f.write(...) etc
+
+   # Write a dictionary as JSON in gzip format, with a
+   # small (64 byte) window size.
+   config = { ... }
+   with gzip.open("config.gz", "wb") as f:
+       json.dump(config, f)
+
+For guidance on working with gzip sources and choosing the window size see the
+note at the :ref:`end of the deflate documentation <deflate_wbits>`.