Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:4/4
K:E
['A4 =G2']  
X:1
L:1/8
M:4/4
K:E
 =G3 F E2 G2 | A4 =G2 EF | =G3 F E2 G2 | A4 =G2 AB | =c3 B A2 =G2 | A4 =G2 G2 | A3 =G F2 E2 | 
 F4 E2 F=G | A3 =G F2 E2 | F4 E2 z2 |]  