Add a note that apply() is needed since the extended call syntax is

completely equivalent.

Doc/lib/libfuncs.tex

@@ -75,6 +75,8 @@ def my_import(name):
   \code{\var{function}(\var{args})}, since in that case there is always
   exactly one argument.  The use of \function{apply()} is equivalent
   to \code{\var{function}(*\var{args}, **\var{keywords})}.
+  Use of \function{apply()} is not necessary since the ``extended call
+  syntax,'' as used in the last example, is completely equivalent.
 \end{funcdesc}
 
 \begin{funcdesc}{bool}{x}