Backport the following changes: Misc/NEWS 1.387->1.388 Lib/test/string_tests.py 1.10->1.11, 1.12->1.14, Lib/test/test_unicode.py 1.50->1.51, 1.53->1.54, 1.55->1.56 Lib/test/test_string.py 1.15->1.16 Lib/string.py 1.61->1.63 Lib/test/test_userstring.py 1.5->1.6, 1.11, 1.12 Objects/stringobject.c 2.156->2.159 Objects/unicodeobject.c 2.137->2.139 Doc/lib/libstdtypes.tec 1.87->1.88 Add a method zfill to str, unicode and UserString and change Lib/string.py accordingly (see SF patch http://www.python.org/sf/536241) This also adds Guido's fix to test_userstring.py and the subinstance checks in test_string.py and test_unicode.py.

--- a/Doc/lib/libstdtypes.tex	Mon Apr 22 11:21:59 2002 +0000
+++ b/Doc/lib/libstdtypes.tex	Mon Apr 22 11:57:06 2002 +0000
@@ -689,6 +689,12 @@
 Return a copy of the string converted to uppercase.
 \end{methoddesc}
 
+\begin{methoddesc}[string]{zfill}{width}
+Return the numeric string left filled with zeros in a string
+of length \var{width}. The original string is returned if
+\var{width} is less than \code{len(\var{s})}.
+\end{methoddesc}
+
 
 \subsubsection{String Formatting Operations \label{typesseq-strings}}