Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
M:9/8
K:D
['FAA FAB', 'A f3 efe d2 e f3 def']  
X:1
L:1/8
M:9/8
K:D
 FAA FAB AFD | FAA FAB d2 A | FAA FAB AFD | f3 edc B2 A |: f3 efe d2 e | f3 def gfe | f3 dfd d2 A | 
 BAF DFA B2 A :|  