From 32b003aca3e9d670367bd62cbf355ee61fa6b308 Mon Sep 17 00:00:00 2001
From: "Miss Islington (bot)"
 <31488909+miss-islington@users.noreply.github.com>
Date: Tue, 21 Nov 2017 00:29:34 -0800
Subject: [PATCH] Add comment and improve variable name in roundrobin()
 (GH-4486) (#4487)

(cherry picked from commit 337cbbace0a43f50fcd33ea4d3b7cb30733237db)
---
 Doc/library/itertools.rst | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/Doc/library/itertools.rst b/Doc/library/itertools.rst
index 86a590bb67..594af39f60 100644
--- a/Doc/library/itertools.rst
+++ b/Doc/library/itertools.rst
@@ -753,15 +753,16 @@ which incur interpreter overhead.
    def roundrobin(*iterables):
        "roundrobin('ABC', 'D', 'EF') --> A D E B F C"
        # Recipe credited to George Sakkis
-       pending = len(iterables)
+       num_active = len(iterables)
        nexts = cycle(iter(it).__next__ for it in iterables)
-       while pending:
+       while num_active:
            try:
                for next in nexts:
                    yield next()
            except StopIteration:
-               pending -= 1
-               nexts = cycle(islice(nexts, pending))
+               # Remove the iterator we just exhausted from the cycle.
+               num_active -= 1
+               nexts = cycle(islice(nexts, num_active))
 
    def partition(pred, iterable):
        'Use a predicate to partition entries into false entries and true entries'
-- 
2.40.0