Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
Q:1/2=80
M:4/4
K:D
['A>G F2 A2 (3(BcB) A2 d>ef>d (3(BcB)', 'f>g a>fd>f a>fd>f d>ef>d (3(BcB) A>G F>Ad>A']  
X:1
L:1/8
Q:1/2=80
M:4/4
K:D
 A>G | F2 A2 (3(BcB) A2 | d>ef>d (3(BcB) A>G | F>Ad>A B>cd>f | e2 e2 e2 A>G | F2 A2 (3(BcB) A2 | 
 d>ef>d (3(BcB) A>G | F>Ad>A B>cd>f | e2 e2 d2 :: f>g | a>fd>f a>fd>f | d>ef>d (3(BcB) A>G | 
 F>Ad>A B>cd>f | e2 e>f e2 f>g | a>fd>f a>fd>f | d>ef>d (3(BcB) A>G | F>Ad>A B>cd>f | e2 e2 d2 :|  