diff --git a/PCbuild/field3.py b/PCbuild/field3.py
new file mode 100644
index 0000000..47f24ca
--- /dev/null
+++ b/PCbuild/field3.py
@@ -0,0 +1,35 @@
+# An absurd workaround for the lack of arithmetic in MS's resource compiler.
+# After building Python, run this, then paste the output into the appropriate
+# part of PC\python_nt.rc.
+# Example output:
+#
+# * For 2.3a0,
+# * PY_MICRO_VERSION = 0
+# * PY_RELEASE_LEVEL = 'alpha' = 0xA
+# * PY_RELEASE_SERIAL = 1
+# *
+# * and 0*1000 + 10*10 + 1 = 101.
+# */
+# #define FIELD3 101
+
+import sys
+
+major, minor, micro, level, serial = sys.version_info
+levelnum = {'alpha': 0xA,
+            'beta': 0xB,
+            'candidate': 0xC,
+            'final': 0xF,
+           }[level]
+string = sys.version.split()[0] # like '2.3a0'
+
+print " * For %s," % string
+print " * PY_MICRO_VERSION = %d" % micro
+print " * PY_RELEASE_LEVEL = %r = %s" % (level, hex(levelnum))
+print " * PY_RELEASE_SERIAL = %d" % serial
+print " *"
+
+field3 = micro * 1000 + levelnum * 10 + serial
+
+print " * and %d*1000 + %d*10 + %d = %d" % (micro, levelnum, serial, field3)
+print " */"
+print "#define FIELD3", field3