Compose a piece of music using the specified alphabetical notation system and the provided theme.
X:1
L:1/8
M:2/4
K:D
['ag fe df Ad ce Bc', 'aA Bc']  
X:1
L:1/8
M:2/4
K:D
|: ag fe | df Ad | ce Bc | df Af | ag fe | df Ad | ce Bc |1 d2 df :|2 d2 dB |: Ad de | fg aA | 
 Bc BA | ec BA | Ad de | fg aA | Bc Bc |1 d2 dB :|2 d2 df ||  