Apply diff2.txt from SF patch http://www.python.org/sf/572113
(with one small bugfix in bgen/bgen/scantools.py)

This replaces string module functions with string methods
for the stuff in the Tools directory. Several uses of
string.letters etc. are still remaining.
diff --git a/Tools/scripts/byteyears.py b/Tools/scripts/byteyears.py
index f67be70..2b0f9b2 100755
--- a/Tools/scripts/byteyears.py
+++ b/Tools/scripts/byteyears.py
@@ -7,7 +7,6 @@
 # Options -[amc] select atime, mtime (default) or ctime as age.
 
 import sys, os, time
-import string
 from stat import *
 
 # Use lstat() to stat files if it exists, else stat()
@@ -51,7 +50,7 @@
         size = st[ST_SIZE]
         age = now - anytime
         byteyears = float(size) * float(age) / secs_per_year
-        print string.ljust(file, maxlen),
-        print string.rjust(`int(byteyears)`, 8)
+        print file.ljust(maxlen),
+        print repr(int(byteyears)).rjust(8)
 
 sys.exit(status)