Assemble a piece of music by merging the alphabetic representation of the predetermined musical pattern and the provided melodic theme.
X:1
L:1/8
M:4/4
K:G
['G2 BG DGBd', 'dega bg g2 agbg', 'G3 B', 'dB B2', 'g2 agbg']  
X:1
L:1/8
M:4/4
K:G
 G2 BG DGBd | dBeB dBAF | G2 BG DGBd | dBAB GEDE | G2 BG DGBd | dBeB dBAB | GB B2 dB B2 | 
 dBAB GEDE :: dega bg g2 | agbg ageg | dega bage | dBAB GE D2 | dega bg g2 | agbg agef | 
 g2 fg efge | dBAB GEDE :|"^variations" |: G3 B dB B2 | dBeB dBAB | G3 B dB B2 | dBAB GEDE | 
 G3 B dB B2 | dBeB dBAB | GB B2 dB B2 | dBAB GEDE :: dega bg g2 | agbg ageg | dega bage | 
 dBAB GE D2 | dega bg g2 | agbg agef | g2 fg efge | dBAB GEDE :|  