fragmentSingleValue will fragments the first argument into a max. number of pieces (given by the second argument) of length from the third; the last one may be shorter. All arguments are treated like constants.
mapping for field list1:
Single value with total 30 characters length is fragment to maximum 10 pieces. Each piece is 4 characters length.
8 pieces will be created, due to 30 divide by 4 will 7.5, round up is 8.
Last piece (8th) is shorter because only remain 2 characters, after 30 minus 28(4 time 7) = 2.