Compose a musical piece using the designated musical pattern's alphabetic representation and the assigned melodic theme.
X:1
L:1/8
M:4/4
K:D
['dBAF A2 FA', 'B2 BA B2']  
X:1
L:1/8
M:4/4
K:D
|: dBAF A2 FA | dBAF EF D2 | dBAF A2 FA |1 B2 BA B2 AB :|2 B2 BA B2 dB |: ABde fddf | gefd edBd | 
 ABde fded |1 B2 BA B2 dB :|2 B2 BA B2 AB ||  