Compose a musical piece using the designated musical pattern's alphabetic representation and the assigned melodic theme.
X:1
L:1/8
M:6/8
K:D
['gec d2', 'gec d2']  
X:1
L:1/8
M:6/8
K:D
|: fdd cAc | BGB A2 F | DFA def | g3 efg | fed cBA | BdB A2 G | FAA def |1 gec d2 e :|2 gec d2 A |: 
 FAA BAG | FAA Bcd | F2 A def | g3 efg | fed cBA | BAG A2 G | FAA def |1 gec d2 A :|2 gec d2 e ||  