Remove regsub, reconvert, regex, regex_syntax and everything under lib-old.
diff --git a/Demo/scripts/mboxconvert.py b/Demo/scripts/mboxconvert.py
index 502d774..8c462f3 100755
--- a/Demo/scripts/mboxconvert.py
+++ b/Demo/scripts/mboxconvert.py
@@ -10,7 +10,7 @@
 import os
 import stat
 import getopt
-import regex
+import re
 
 def main():
     dofile = mmdf
@@ -45,7 +45,7 @@
     if sts:
         sys.exit(sts)
 
-numeric = regex.compile('[1-9][0-9]*')
+numeric = re.compile('[1-9][0-9]*')
 
 def mh(dir):
     sts = 0