Bump version number to 2.3b1.
diff --git a/PC/python_nt.rc b/PC/python_nt.rc
index 69415ca..801ae29 100644
--- a/PC/python_nt.rc
+++ b/PC/python_nt.rc
@@ -33,14 +33,14 @@
  * but that neither gives an error nor comes anywhere close to working.  The
  * following comment and #define are output from PCbuild\field3.py:
  *
- * For 2.3a2,
+ * For 2.3b1,
  * PY_MICRO_VERSION = 0
- * PY_RELEASE_LEVEL = 'alpha' = 0xa
- * PY_RELEASE_SERIAL = 2
+ * PY_RELEASE_LEVEL = 'beta' = 0xb
+ * PY_RELEASE_SERIAL = 1
  *
- * and 0*1000 + 10*10 + 2 = 102
+ * and 0*1000 + 11*10 + 1 = 111
  */
-#define FIELD3 102
+#define FIELD3 111
 
 /* e.g., 2.1a2
  * PY_VERSION comes from patchevel.h