Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
M:4/4
K:A
['A<A A2', '(a>A)(g>A) (f>A)(e>c)']  
X:1
L:1/8
M:4/4
K:A
 E |O A<A A2 (F>A)E>c | d>B d/c/B/A/ G<BB>c | A<A A2 (F>A)E>c | (3def (3efg (3aed (3cdB | 
 A<A A2 (F>A)E>c | d>B d/c/B/A/ G<BB>c | A<A A2 F>AE>c | (3def (3efg a<AA || g | 
 (a>A)(g>A) (f>A)(e>c) | d>B d/c/B/A/ G<BB>g | (a>A)(g>A) (f>A)(e>c) | (3def (3efg a<AA>g | 
 (3faf (3geg (3fdf (3ece | d>B d/c/B/A/ G<BB>A | (C>E) (3EAc (D>F) (3FAc | 
 (3def (3efg (3aed (3cdBO ||  