Generate a piece of music.  
X:1
T:Music21 Fragment
C:Music21
L:1/4
M:none
I:linebreak $
K:none
V:1 treble 
V:1
{/C} G G{/G} E F | E C2 B, | G,2 B, B, | C2 E F ||{/F} G !turn!G{/G} E F | E/ D/ C2 B, | %6
 G,2 B, B, | C2 E E ||{/D} B, C{/F} E F | G2 c B | G G E F | E2 C C || %12  