Fix doc compilation problem.

Doc/lib/libstdtypes.tex

@@ -654,7 +654,7 @@ For 8-bit strings, this method is locale-dependent.
 \end{methoddesc}
 
 \begin{methoddesc}[str]{isidentifier}{}
-Return True if S is a valid identifier according\n\
+Return True if S is a valid identifier according
 to the language definition.
 \end{methoddesc}