[Python-checkins] bpo-38771: Explict test for None in code example (GH-17108) (GH-17109)

[Raymond Hettinger]

https://github.com/python/cpython/commit/d8e08456025d9349abbf76035c821d3f7b2d722a
commit: d8e08456025d9349abbf76035c821d3f7b2d722a
branch: 3.8
author: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
committer: Raymond Hettinger <rhettinger at users.noreply.github.com>
date: 2019-11-11T16:59:14-08:00
summary:

bpo-38771:  Explict test for None in code example (GH-17108) (GH-17109)

(cherry picked from commit 98480cef9dba04794bd61c7e7cca643d384c8c35)

Co-authored-by: Jonathan Scholbach <j.scholbach at posteo.de>

files:
M Doc/library/collections.rst

diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst
index 90a3f4bea9a45..a5e8d04099b22 100644
--- a/Doc/library/collections.rst
+++ b/Doc/library/collections.rst
@@ -162,7 +162,7 @@ environment variables which in turn take precedence over default values::
         parser.add_argument('-u', '--user')
         parser.add_argument('-c', '--color')
         namespace = parser.parse_args()
-        command_line_args = {k:v for k, v in vars(namespace).items() if v}
+        command_line_args = {k: v for k, v in vars(namespace).items() if v is not None}
 
         combined = ChainMap(command_line_args, os.environ, defaults)
         print(combined['color'])