On a basic level the program below would accomplish that (can't promise this sounds pleasing to the ear ;) -

start

chunk lefthand

play C3, Eb3, G3 for 2b

rest for 2b

endchunk

chunk righthand

play C3 for 1b

play Gb3 for 1b

play Eb3 for 1b

play Db3 for 1b

endchunk

run lefthand with loop for 100

run righthand with loop for 100

finish