Issue #15677: Document that zlib and gzip accept a compression level of 0 to mean 'no compression'.
Patch by Brian Brazil.
diff --git a/Doc/library/gzip.rst b/Doc/library/gzip.rst
index 9422ea9..abbd018 100644
--- a/Doc/library/gzip.rst
+++ b/Doc/library/gzip.rst
@@ -50,9 +50,10 @@
supported. If you need to read a compressed file in text mode, wrap your
:class:`GzipFile` with an :class:`io.TextIOWrapper`.
- The *compresslevel* argument is an integer from ``1`` to ``9`` controlling the
- level of compression; ``1`` is fastest and produces the least compression, and
- ``9`` is slowest and produces the most compression. The default is ``9``.
+ The *compresslevel* argument is an integer from ``0`` to ``9`` controlling
+ the level of compression; ``1`` is fastest and produces the least
+ compression, and ``9`` is slowest and produces the most compression. ``0``
+ is no compression. The default is ``9``.
The *mtime* argument is an optional numeric timestamp to be written to
the stream when compressing. All :program:`gzip` compressed streams are