ntpath.samefile fails to detect that "A.TXT" and "a.txt" refer to the same file on Windows XP.

Noticed while researching a buildbot failure due to a patch for issue #10684.

Lib/ntpath.py

@@ -654,7 +654,7 @@ except (AttributeError, ImportError):
     # Non-Windows operating systems fake this method with an XP
     # approximation.
     def _getfinalpathname(f):
-        return abspath(f)
+        return normcase(abspath(f))
 
 def samefile(f1, f2):
     "Test whether two pathnames reference the same actual file"

Misc/NEWS

@@ -83,6 +83,9 @@ Core and Builtins
 Library
 -------
 
+- ntpath.samefile failed to notice that "a.txt" and "A.TXT" refer to the same
+  file on Windows XP. As noticed in issue #10684.
+
 - Issue #12000: When a SSL certificate has a subjectAltName without any
   dNSName entry, ssl.match_hostname() should use the subject's commonName.
   Patch by Nicolas Bareil.