Produce music using the specified musical structure depicted in letters along with the provided musical theme.
X:1
L:1/4
M:4/4
K:G
['B B']  
X:1
L:1/4
M:4/4
K:G
 z G G A | B4- | B B c B | B A3- | A A A B | c4- | c d e d | d B3- | B d d d | g4- | g g f e | 
 e d3- | d B B e | d4- | d B c A | G4- | G z3 |]  