Craft a musical piece that abides by the prescribed structural guidelines and the given theme.
X:1
L:1/8
M:6/8
K:Amix
['cBA ecA fed cBA', 'cBA def gfg B3 Bfg agf gfe'  
X:1
L:1/8
M:6/8
K:Amix
 cBA ecA | fed cBA | def gfg | B3 Bed | cBA ecA | fed cBA | c2 e dBG |1 ABA Aed :|2 ABA Afg |: 
 agf gfe | fed cBA | def gfg | B3 Bfg | agf gfe | fed cBA | c2 e dBG |1 ABA Afg :|2 ABA Aed ||  