Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
M:2/4
K:D
['A B2 A>^G A2 (3ABc d>cdA G2', 'z!fine! A defg a2 fa gfga g2{ag}']  
X:1
L:1/8
M:2/4
K:D
 A | B2 A>^G | A2 (3ABc | d>cdA | G2 FG | A2 fd | cA BG | F2 D>D | D2 z!fine! || A | defg | a2 fa | 
 gfga | g2{ag} fe | defg | agfe | f2 d>d | defg | agfa | g2 fe | fdcA | f2 ed | cA BG | FBAG | 
 F2 D>D | D2!D.C.! ||  