Compose a musical piece using the designated musical pattern's alphabetic representation and the assigned melodic theme.
X:1
L:1/4
M:4/4
K:D
['E C D3']  
X:1
L:1/4
M:4/4
K:D
 A | (A3/2 F/) G A | B2 G B | (A3/2 G/) E C | D3 D/D/ | (C E) G A | (c B) d ^G | A3 A/ F/ | 
 D F A A | d2 e c | (B G) E C | D3 A/ A/ | c2 d B | A3/2 F/ G C | D3 ||  