Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
M:2/2
K:Gmix
['DG G2', 'G2 dG']  
X:1
L:1/8
M:2/2
K:Gmix
 DG G2 DF F2 | DG G2 dGcF | DGGF D3 E | F2 AF CFAF :| G2 dG eGdG | G2 dG cAFA | G2 dG eGdB | 
 c2 AF CFAF | G2 dG eGdG | eGdG cAFA | dcde fefd | c2 AF CFAF ||  