Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/8
M:9/8
K:F
['F3 AFA cAc', 'a3 afd', 'cAF cAF Acf']  
X:1
L:1/8
M:9/8
K:F
 F3 AFA cAc | F3 dBd G3 | F3 AFA cAc | def gfe f3 :: a3 afd afd | efg gec gec | a3 afd gec | 
 def gfe f3 :: cAF cAF Acf | dBG dBG Bdg | cAF cAF Acf | cBA GFE F3 :|  