gh-146061: Fix contradicting sentences in json docs

Doc/library/json.rst

@@ -211,7 +211,9 @@ Basic Usage
       a string (such as ``"\t"``) is used to indent each level.
       If zero, negative, or ``""`` (the empty string),
       only newlines are inserted.
-      If ``None`` (the default), the most compact representation is used.
+      If ``None`` (the default), no pretty printing is done, and a
+      compact representation is used, though a singular space is 
+      still left after the separators.
    :type indent: int | str | None
 
    :param separators: