diff -r 3f9e68864ccc -r b3a677c82a35 mercurial/__init__.py
--- a/mercurial/__init__.py	Sat May 14 19:52:00 2016 +0900
+++ b/mercurial/__init__.py	Wed Mar 09 19:55:45 2016 +0000
@@ -12,36 +12,13 @@
 import sys
 import zipimport
 
+from . import (
+    policy
+)
+
 __all__ = []
 
-# Rules for how modules can be loaded. Values are:
-#
-#    c - require C extensions
-#    allow - allow pure Python implementation when C loading fails
-#    py - only load pure Python modules
-#
-# By default, require the C extensions for performance reasons.
-modulepolicy = 'c'
-try:
-    from . import __modulepolicy__
-    modulepolicy = __modulepolicy__.modulepolicy
-except ImportError:
-    pass
-
-# PyPy doesn't load C extensions.
-#
-# The canonical way to do this is to test platform.python_implementation().
-# But we don't import platform and don't bloat for it here.
-if '__pypy__' in sys.builtin_module_names:
-    modulepolicy = 'py'
-
-# Our C extensions aren't yet compatible with Python 3. So use pure Python
-# on Python 3 for now.
-if sys.version_info[0] >= 3:
-    modulepolicy = 'py'
-
-# Environment variable can always force settings.
-modulepolicy = os.environ.get('HGMODULEPOLICY', modulepolicy)
+modulepolicy = policy.policy
 
 # Modules that have both Python and C implementations. See also the
 # set of .py files under mercurial/pure/.