Develop a musical piece by utilizing the alphabet-based notation of the selected musical form and the provided melodic idea.
X:1
L:1/8
M:12/8
K:G
['B2 A', 'gag faf gfg']  
X:1
L:1/8
M:12/8
K:G
 def | gdB B2 A B2 A Bcd | efe edB dBA AB/c/d | gdB B2 A B2 A Bcd | efg fed e3 :| e2 f | 
 gag faf gfg edB | edB Bed BAA A2 e/f/ | gag faf gfg efg | a Bcd e3 :|  