Use python/Lib/xml in example

Author: totosuki

Doc/library/os.rst

@@ -3669,7 +3669,7 @@ features:
 
       import os
       from os.path import join, getsize
-      for root, dirs, files in os.walk('python/Lib'):
+      for root, dirs, files in os.walk('python/Lib/xml'):
           print(root, "consumes", end=" ")
           print(sum(getsize(join(root, name)) for name in files), end=" ")
           print("bytes in", len(files), "non-directory files")
@@ -3730,7 +3730,7 @@ features:
    ``__pycache__`` subdirectory::
 
       import os
-      for root, dirs, files, rootfd in os.fwalk('python/Lib'):
+      for root, dirs, files, rootfd in os.fwalk('python/Lib/xml'):
           print(root, "consumes", end="")
           print(sum([os.stat(name, dir_fd=rootfd).st_size for name in files]),
                 end="")

Lib/os.py

@@ -345,7 +345,7 @@ def walk(top, topdown=True, onerror=None, followlinks=False):
 
     import os
     from os.path import join, getsize
-    for root, dirs, files in os.walk('python/Lib'):
+    for root, dirs, files in os.walk('python/Lib/xml'):
         print(root, "consumes ")
         print(sum(getsize(join(root, name)) for name in files), end=" ")
         print("bytes in", len(files), "non-directory files")
@@ -460,7 +460,7 @@ def fwalk(top=".", topdown=True, onerror=None, *, follow_symlinks=False, dir_fd=
         Example:
 
         import os
-        for root, dirs, files, rootfd in os.fwalk('python/Lib'):
+        for root, dirs, files, rootfd in os.fwalk('python/Lib/xml'):
             print(root, "consumes", end="")
             print(sum(os.stat(name, dir_fd=rootfd).st_size for name in files),
                   end="")