#16333: document a way to get rid of trailing whitespace when indent is used.
diff --git a/Doc/library/json.rst b/Doc/library/json.rst
index f9547cb..bdb6436 100644
--- a/Doc/library/json.rst
+++ b/Doc/library/json.rst
@@ -42,7 +42,8 @@
 Pretty printing::
 
     >>> import json
-    >>> print(json.dumps({'4': 5, '6': 7}, sort_keys=True, indent=4))
+    >>> print(json.dumps({'4': 5, '6': 7}, sort_keys=True,
+    ...                  indent=4, separators=(',', ': ')))
     {
         "4": 5,
         "6": 7
@@ -155,6 +156,12 @@
    .. versionchanged:: 3.2
       Allow strings for *indent* in addition to integers.
 
+   .. note::
+
+      Since the default item separator is ``', '``,  the output might include
+      trailing whitespace when *indent* is specified.  You can use
+      ``separators=(',', ': ')`` to avoid this.
+
    If *separators* is an ``(item_separator, dict_separator)`` tuple, then it
    will be used instead of the default ``(', ', ': ')`` separators.  ``(',',
    ':')`` is the most compact JSON representation.
@@ -393,6 +400,12 @@
    .. versionchanged:: 3.2
       Allow strings for *indent* in addition to integers.
 
+   .. note::
+
+      Since the default item separator is ``', '``,  the output might include
+      trailing whitespace when *indent* is specified.  You can use
+      ``separators=(',', ': ')`` to avoid this.
+
    If specified, *separators* should be an ``(item_separator, key_separator)``
    tuple.  The default is ``(', ', ': ')``.  To get the most compact JSON
    representation, you should specify ``(',', ':')`` to eliminate whitespace.