Compose a piece of music by integrating the assigned letter representation and provided tune.
X:1
L:1/8
M:4/4
K:D
['defg afdf']  
X:1
L:1/8
M:4/4
K:D
|: defg afdf | afdf e B3 | defg afdf | abaf ee dB | defg afdf | afdf eBBA | B3 A FAdB | 
 AFDF ED BA :|  