Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
M:6/8
K:D
['F ABA FDF ABA F2 D/F/ A3']  
X:1
L:1/8
M:6/8
K:D
 F | ABA FDF | ABA F2 D/F/ | A3 B3 | G3/2 F/ G E2 F | GAG ECE | GFE B3 | AAA A2 G | F3/2 E/ F D2 |]  