Construct a musical piece by amalgamating the designated alphabetical representation and the supplied musical theme.
X:1
L:1/4
M:2/2
K:G
['G,3/2 A,/']  
X:1
L:1/4
M:2/2
K:G
 A/ | [BD]2 c/B/A/ G | [AD]2 [AD]/B/ ^c | d d (3(B/^c/B/) A | G2 F G | [AD] [AD] [BD] G | F D E C | 
 B,2 G,3/2 A,/ | G,3 z | G,3/2 A,/ B, C | D D{A} B G | F3/2 G/ A/G/ F | G3- G | G,3/2 A,/ B, C | 
 [DG,] [DG,] [EG,] C/ | B2 G,3/2 A,/ | G,3 z |]  