bpo-26330: Update shutil.disk_usage() documentation (GH-5184)

Clarify that on Windows, path must be a directory.
On Unix, path can be a file or a directory.

diff --git a/Doc/library/shutil.rst b/Doc/library/shutil.rst
index 2b84fa2937284c41cf501e74ffeae8a08c167224..1527deb167f1e3eb1ba4eb40d28085a22a752b22 100644 (file)
--- a/Doc/library/shutil.rst
+++ b/Doc/library/shutil.rst
@@ -318,7 +318,8 @@ Directory and files operations
 
    Return disk usage statistics about the given path as a :term:`named tuple`
    with the attributes *total*, *used* and *free*, which are the amount of
-   total, used and free space, in bytes.
+   total, used and free space, in bytes.  On Windows, *path* must be a
+   directory; on Unix, it can be a file or directory.
 
    .. versionadded:: 3.3