Craft a piece of music that integrates both the suggested theme and letter-based structure.
X:1
L:1/16
M:2/4
K:G
['d2 gabg efge dBge dBGB (3AAA (AB)', 'cdef gabg efge dBge dBGB (3AAA (AB)', 'g2 d2 dggf g2(gf) gaba gfed eaab', 'gfed dggf g2(gf) edBg eBGB (3AAA (AB)']  
X:1
L:1/16
M:2/4
K:G
 d2 | gabg efge | dBge dBGB | (3AAA (AB) AGAB | cBAB cdef || gabg efge | dBge dBGB | 
 (3AAA (AB) AGAB | cdef g2 :: d2 | dggf g2(gf) | gaba gfed | eaab a2(ag) | agba gfed || 
 dggf g2(gf) | edBg eBGB | (3AAA (AB) AGAB | cdef g2 :|  