Develop a musical composition using the outlined alphabetical depiction of the structure and the provided theme.
X:1
L:1/8
Q:3/8=120
M:6/8
K:D
['d dcd e2', 'd2 d']  
X:1
L:1/8
Q:3/8=120
M:6/8
K:D
 A2 d dcd | e2 e e2 g | f2 d dcd | e2 c A2 z | A2 d dcd | e2 e e2 g | f2 d edc | d2 d d3 :: 
 a2 a agf | g2 a b3 | g2 g gfe | f2 g a3 | d2 d B2 B | e2 e c2 c | f2 f d2 d |"^D.Capo" g2 f e3 |]  