Added a try except protection when searching for list index, also made input a textarea and two maxlengths of 3 and 480 to keep only 3 char captcha entry and 480 char requests the 480 char will keep it inside of the 500 byte limit for StringProperty and keep it searchable  One problem is chinese chars of 480 units might be over 1400 bytes  the GAE dev server accepts and displays these too long entries but the book says 500 bytes.  The 480 maxlength will keep ascii and most clients under 500.