mercurial/demandimport.py

--- a/mercurial/demandimport.py	Tue Sep 27 22:36:00 2016 +0900
+++ b/mercurial/demandimport.py	Tue Sep 27 21:56:00 2016 +0900
@@ -264,6 +264,7 @@
     '_imp',
     '_xmlplus',
     'fcntl',
+    'nt', # pathlib2 tests the existence of built-in 'nt' module
     'win32com.gen_py',
     '_winreg', # 2.7 mimetypes needs immediate ImportError
     'pythoncom',