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:G
['GAB BAG', 'd g2 d']  
X:1
L:1/8
M:6/8
K:G
 D | GAB BAG | ded d2 c | B3 BAG | A3 DFA | GAB BAG | c2 d ege | dBG AGE | G3 G2 :: d | g2 d g2 d | 
 c3 c2 d | g2 d g2 d | A3 DFA | g2 a gdB | c2 d ege | dBG AGE | G3 G2 :|  