Craft a piece of music that integrates both the suggested theme and letter-based structure.
X:1
L:1/8
M:2/4
K:D
['|{e} dc{e} dc |{e}', 'df ag ec e2']  
X:1
L:1/8
M:2/4
K:D
|: A |{e} dc{e} dc |{e} dc df |{a} gf ga | b2 a z |{e} dc{e} dc |{e} dc df | ag ec | e2 d :: f | 
 ag eg | ba fd | ag eg | ba fd |{e} dc{e} dc |{e} dc df | ag ec | e2 d :|  