Develop a musical composition by utilizing the given alphabetic notation and supplied motif.
X:1
L:1/8
M:2/2
K:Amix
['g2 dB', 'cAA g dGdB dGGg dGdB cAAg dGdB']  
X:1
L:1/8
M:2/2
K:Amix
 f | g2 dB gBBf | g2 eB aAAf | g2 dB g2 af | gedB cAA :: g | dGdB dGGg | dGdB cAAg | dGdB efga | 
 gedB cAA :|  