Patch #1517490: fix glitches in filter() docs.
diff --git a/Doc/lib/libfuncs.tex b/Doc/lib/libfuncs.tex
index 6b7a688..38eeaf1 100644
--- a/Doc/lib/libfuncs.tex
+++ b/Doc/lib/libfuncs.tex
@@ -468,10 +468,10 @@
Construct a list from those elements of \var{list} for which
\var{function} returns true. \var{list} may be either a sequence, a
container which supports iteration, or an iterator, If \var{list}
- is a string or a tuple, the result also has that type; otherwise it
- is always a list. If \var{function} is \code{None}, the identity
- function is assumed, that is, all elements of \var{list} that are false
- (zero or empty) are removed.
+ is a string (either \code{str} or \code{unicode}) or a tuple, the result
+ also has that type; otherwise it is always a list. If \var{function} is
+ \code{None}, the identity function is assumed, that is, all elements of
+ \var{list} that are false are removed.
Note that \code{filter(function, \var{list})} is equivalent to
\code{[item for item in \var{list} if function(item)]} if function is