SF bug #1048756, Doc typo for pdb

Doc/lib/libpdb.tex

@@ -285,7 +285,7 @@ command --- this executes the Python \keyword{print} statement.}
 
 \item[pp \var{expression}]
 
-Like the \samp{p} command, except the value of the exception is
+Like the \samp{p} command, except the value of the expression is
 pretty-printed using the \module{pprint} module.
 
 \item[alias \optional{\var{name} \optional{command}}]