Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:6/8
K:D
['d2 D', 'e3 A3 AB=c Bd=c BAG B3 B^cd']  
X:1
L:1/8
M:6/8
K:D
 d2 D d2 D | BAG FED | FGA Bcd | efd{d} cBA | d2 D d2 D | BAG FED | FGA Bcd | egf{f} e3 :: 
 A3 AB=c | Bd=c BAG | B3 B^cd | ced{d} cBA | a2 A g2 G | f2 F e2 E | d2 D FGA | Bdc d3 :|  