Create a musical composition employing the given alphabetic structure and melodic theme.
X:1
L:1/8
M:4/4
K:G
['G2 d^c dB=cA =F3 A dBcB Azd^c', 'z fgag fdeg fdcA BGBd fzgf fede']  
X:1
L:1/8
M:4/4
K:G
 G2 d^c dB=cA | =F3 A dBcB | Azd^c dfeg |1 fdcA BdcA :|2 fdcA BGBd || fzgf fede | fgag fdd z | 
 fgag fdeg | fdcA BGBd | fzgf fede | fgag fdd z | fg g2 g2 ag | fdcA BdcA ||  