Create a musical composition based on the alphabetic representation of the predetermined pattern and the given melodic theme.
X:1
L:1/8
M:4/4
K:G
['D3 E G3 B', 'c2 ec B2 dB AGAB']  
X:1
L:1/8
M:4/4
K:G
 z2 | D3 E G3 B | AGAB AG E2 | D3 E G3 B | AGAB G2 :| AB | c2 ec B2 dB | AGAB AG E2 | c2 ec B2 dB | 
 AGAB G2 AB | c2 ec B2 dB | AGAB AG E2 | D3 E G3 B | AGAB G2 |]  