Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:2/4
K:G
['B/c/ |{^c} d2 e/d/c/d/', 'AA cA BA dBG B/c/ |{^c} d2', 'e2 GG (3GAB cc (3cde (3def (3GAB']  
X:1
L:1/8
M:2/4
K:G
 B/c/ |{^c} d2 e/d/c/d/ | g2 e/d/^c/d/ | cc/e/ BB/d/ | AAA B/c/ |{^c} d2 e/d/c/d/ | gg e/d/^c/d/ | 
 cc de/f/ | g2 z :| gdd B/d/ | d/c/A AA | cA BA | dBG B/c/ |{^c} d2 e/d/c/d/ | dgB B/d/ | 
 cc de/f/ | g2 z :|[K:C]"^Trio" GG (3GAB | cc (3cde | dd (3def | gg e2 | GG (3GAB | cc (3cde | 
 (3def (3GAB | c2 z :|  