Style nit.

Doc/lib/libitertools.tex

@@ -133,7 +133,7 @@ by functions or loops that truncate the stream.
 
 \begin{funcdesc}{groupby}{iterable\optional{, key}}
   Make an iterator that returns consecutive keys and groups from the
-  \var{iterable}.  \var{key} is a function computing a key value for each
+  \var{iterable}. The \var{key} is a function computing a key value for each
   element.  If not specified or is \code{None}, \var{key} defaults to an
   identity function and returns  the element unchanged.  Generally, the
   iterable needs to already be sorted on the same key function.
@@ -332,7 +332,7 @@ by functions or loops that truncate the stream.
 
 \begin{funcdesc}{tee}{iterable\optional{, n=2}}
   Return \var{n} independent iterators from a single iterable.
-  The case where \var{n} is two is equivalent to:
+  The case where \code{n==2} is equivalent to:
 
   \begin{verbatim}
      def tee(iterable):