Force the Python host version on Mac OS X
diff --git a/setup.py b/setup.py
index 2441445..b43ec9a 100644
--- a/setup.py
+++ b/setup.py
@@ -30,10 +30,12 @@
 """A setup module for the GRPC Python package."""
 
 from distutils import extension as _extension
+from distutils import util
 import os
 import os.path
 import pkg_resources
 import platform
+import re
 import shlex
 import shutil
 import sys
@@ -133,6 +135,10 @@
   if mac_target and (pkg_resources.parse_version(mac_target) <
                      pkg_resources.parse_version('10.7.0')):
     os.environ['MACOSX_DEPLOYMENT_TARGET'] = '10.7'
+    os.environ['_PYTHON_HOST_PLATFORM'] = re.sub(
+        r'macosx-[0-9]+\.[0-9]+-(.+)',
+        r'macosx-10.7-\1',
+        util.get_platform())
 
 
 def cython_extensions(module_names, extra_sources, include_dirs,