Create a composition by utilizing the given alphabet-based musical pattern and the provided melodic theme.
X:1
L:1/8
M:2/2
K:Amix
['a2 a2 A2 AB AGcA GECD']  
X:1
L:1/8
M:2/2
K:Amix
|:"A" ceef edcd | efed cB A2 |"G" BGAB dedB | GBeB d=c B2 |"A" ceef edcd | efed cdeg | 
"G" gfed cBAF |"E7" EFAB"A" A4 :| |]:[K:Amin]"Am" a2 a2 A2 AB |"C" =cedc"Am" AGcA |"C" GECD EGAB | 
 cdeg ed e2 |"Am" a2 a2 A2 AB |"C" cedc"Am" AGcA |"C" GECD EDEf |"E7" eCDC"Am" A4 :|  