Generate a piece of music. It is monophony.  
X:1
T:Music21 Fragment
C:Music21
L:1/8
Q:1/4=86
M:2/4
I:linebreak $
K:C
V:1 treble 
V:1
 G/G/ | EG GG | c2 GG | EG AG | D3 G | EG GG | A>B cd | e>c dd | c3 z/ G/ | EG GG | c2 GG | EG AG | %12
 D3 G | EG GG | AB cd | ec dd | c3 c | Bd dd | c2 ee | d>c BA | G3 G/G/ | EG GG | A2 cd | e>c dd | %24
 c3 G/G/ | EG z2 | FA z F | EG ce | d3 G/G/ | EG GG | A>B cd | e>c dd | c3 x || %33  