Compose a piece of music using the specified alphabetical notation system and the provided theme.
X:1
L:1/8
M:4/4
K:Bmin
['fB B2', 'dfaf e2']  
X:1
L:1/8
M:4/4
K:Bmin
|: fB B2 fBaB | fB BA d2 de | fB B2 fgfe |1 dfaf e2 de :|2 dfaf e2 fe |: d3 e f3 e | defe dDFA | 
 d3 e fgfe |1 dfaf e2 fe :|2 dfaf e2 de |]  