Adding a warning about the regsub module. This also disables further

warnings in this same module, to prevent getting a warning about
importing regex (we *know* that it's obsolete :-).

Lib/regsub.py

@@ -10,6 +10,13 @@ splitx(str, pat, maxsplit): split string using pattern as delimiter plus
                             return delimiters
 """
 
+import warnings
+warnings.warn("the regsub module is deprecated; please use re.sub()",
+	      DeprecationWarning)
+
+# Ignore further deprecation warnings about this module
+warnings.filterwarnings("ignore", "", DeprecationWarning, __name__)
+
 import regex