diff --git a/Doc/lib/libfuncs.tex b/Doc/lib/libfuncs.tex
index 3937c29..f00d81d 100644
--- a/Doc/lib/libfuncs.tex
+++ b/Doc/lib/libfuncs.tex
@@ -602,7 +602,7 @@
 
 \begin{verbatim}
 >>> import types
->>> if isinstance(x, types.StringType): print "It's a string"
+>>> if type(x) == types.StringType: print "It's a string"
 \end{verbatim}
 \end{funcdesc}