How do I escape slashes the string formatting operator? (or: why is it behaving this way?)

[Dustan]

Python 2.5.2 (r252:60911, Feb 21 2008, 13:11:45) [MSC v.1310 32 bit
(Intel)] on
win32
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>>> 'HELP!%(xyz)/' % {'xyz':' PLEASE! '}
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: unsupported format character '/' (0x2f) at index 11
>>>

It doesn't like the forward slash after the closed parentheses. I
don't know what it is expecting, but I need that slash there
(obviously this is a simplified example).

All help appreciated.