Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/16
M:2/4
K:Dmin
['A2GA G2F2', 'F8 D4']  
X:1
L:1/16
M:2/4
K:Dmin
|:"Dm" D2AG F2F2 | FGFE D4 | D2F2 A2d2 | d2cB A4 |"F" AGcB A2GF |"Gm" G_AGA G4 | 
"Dm" FEEF"Cm" F_EED |"Dm" D8 ::"F" C2FG A4 | A2GA G2F2 | c4"C7" B4 |"F" A2GA G2F2 | z CDE FGAB | 
 cd_ed cBAG |"Dm" FEEF"Cm" F_EED |"Dm" D8 ::"Dm" F8 |"Cm" G2_E2"Dm" D4 | F8 |"Cm" G2_E2"Dm" D4 | 
"F" _edcB AGF=E | FEFA"Gm" G4 |"Dm" FEEF"Cm" F_EED |"Dm" D8 :|  