Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/16
M:2/4
K:D
['', 'dFAF dFAF']  
X:1
L:1/16
M:2/4
K:D
 (A2 |: d2)AG F2AF |[M:3/4] dFAF dFAF dFAF |[M:2/4] [A,E]2([A,E-]2 E2)BB | B2[A,E]2 [A,E]2B2B2 | 
 (Bd)c(B AG)FE |[M:3/4] DEF(G AB)AG F2A2 |1[M:1/4] d2>d2 :|2 d2>(e2 ||[M:2/4] f2)f2 (af)d2 | 
 (fg)af def(d | [Ae]2) e(a f2)ed | B(dAG) F2A2 |1[M:1/4] d2>(e2 :|2 d2>)A2!D.C.! ||  