Fix Windows build.
diff --git a/PC/pyconfig.h b/PC/pyconfig.h
index 314fbf1..4597db0 100644
--- a/PC/pyconfig.h
+++ b/PC/pyconfig.h
@@ -277,7 +277,7 @@
 #	define PY_LONG_LONG __int64
 #	define PY_LLONG_MAX LLONG_MAX
 #	define PY_LLONG_MIN LLONG_MIN
-#	define PY_ULLONG_MIN ULLONG_MIN
+#	define PY_ULLONG_MAX ULLONG_MAX
 #endif
 
 /* For Windows the Python core is in a DLL by default.  Test