Develop a musical composition using the outlined alphabetical depiction of the structure and the provided theme.
X:1
L:1/8
Q:1/8=232
M:4/4
K:D
['dB B2 AB dB GB df g2', 'af gf']  
X:1
L:1/8
Q:1/8=232
M:4/4
K:D
|: dB B2 AB dB | GB df g2 fg | ec dB AB cd | df g^g a2 =ge | dB B2 AB dB | GB df g2 gb | 
 bg af gf ed | ef g^g a2 =ge :: dg gg g2 af | gb af gf ed | ea aa ca aa | Ba ca ag ed | 
 Bg gg gf af | gf ef gf ga | bg af gf ed | ef g^g a2 =ge :|  