Windows:  2.1a1 changes so Python runs again.  Note that the python20
subproject is gone, replaced by the new pythoncore subproject.
diff --git a/PC/config.h b/PC/config.h
index 9b2f918..65d390a 100644
--- a/PC/config.h
+++ b/PC/config.h
@@ -327,9 +327,9 @@
    more (other compilers will still need to do so, but that's taken care
    of by the Distutils, so it's not a problem). */
 #ifdef _DEBUG
-#pragma comment(lib,"python20_d.lib")
+#pragma comment(lib,"python21_d.lib")
 #else
-#pragma comment(lib,"python20.lib")
+#pragma comment(lib,"python21.lib")
 #endif
 #endif /* USE_DL_EXPORT */