Compose a musical piece using the designated musical pattern's alphabetic representation and the assigned melodic theme.
X:1
L:1/4
M:3/4
K:G
['G G']  
X:1
L:1/4
M:3/4
K:G
 G G G | B3/2 A/ G | B B B | d3/2 c/ B | d c B | A2 z | A2 G/F/ | G A B | c2 B/A/ | B c d | 
 d/c/ B A | G2 z |]  