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
['AE E2', 'B2 dB']  
X:1
L:1/8
M:4/4
K:G
|: DEGB AE E2 | AEBE AE E2 | DEGA Bdef | gedB AGEG | DEGB AE E2 | AEBE AE E2 | DEGA Bdef | 
 gedB AGEG :: B2 dB eBdB | B2 dB AGEG | B2 dB eBdB | cABG AGEG | B2 dB eBdB | B2 dB AGEG | 
 g3 f efge | d2 BG AGEG :|  