Craft a musical piece that abides by the prescribed structural guidelines and the given theme.
X:1
L:1/8
M:4/4
K:E
['B3 c', 'c2 ec', 'gefg eccB c2 ec BGFG E2 B,E'  
X:1
L:1/8
M:4/4
K:E
|: B3 c B3 c | BAGF GEGA | BEcE BEcE | BAGE FGAc | BAGA BAGA | BAGF GEGA | B e3 eBce |1 BAGF E4 :|2 
 BAGF E2 ef |: g4 g2 fe | fccB c2 ec | cBBG BGBc | Bceg f2 ef | g2 fe g2 fe | fccB c2 ec | 
 cBBG BGBc |1 Bcef e2 ef :|2 Bcef e4 |: c2 ec c2 ec | BGFG E2 B,E | C E3 EGBc | Bcef gefg | 
 eccB c2 ec | BGFG E2 B,E | C E3 EGBc |1 Bcef e4 :|2 Bcef e2 GA ||  