I am using Python 2.4.2, the latest version currently
available for the system I am using, which is Ubuntu
5.10 for x86.

I was calling the time.strptime() function, and I had
accidentally typed an extra % symbol in the time format
string.  If you do this you get a baffling message in
the traceback.  The deepest frame of the traceback
looks like this:

  File "/usr/lib/python2.4/_strptime.py", line 256, in
pattern
    processed_format = "%s%s%s" % (processed_format,
KeyError: '-'


This means that I accidentally put "%-" in my format
string.

What happens if I accidentally put "% " in my format
string?  This:

  File "/usr/lib/python2.4/_strptime.py", line 256, in
pattern
    processed_format = "%s%s%s" % (processed_format,
KeyError: '\\'

It turns out that spaces in the format string are
replaced by r'\s*' by the time the exception happens. 
It really freaked me out to see Python complaining
about a backslash, when I hadn't put a backslash into
my format string.

I propose that this library call should be re-written
to catch the exception, and then throw a more sensible
exception, including a statement like: "unknown % code
in format string".  In a perfect world this would be
done in such a way that the last frame appearing in the
traceback would be for the call to time.strptime(), and
not show any lines from the guts of time.strptime()
about regular expression compiling.

Logged In: YES 
user_id=357491

Rev. 41376 has the fix in the trunk.  I am not going to
backport since it is a semantic change.

Thanks, Steve.