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
{/^F} G G c2 | c c d c | c c B G | G c B B ||{/C} B, C E F | G2 B c | B/ c/ e/ d/ c/ B/ A/ G/ | %7
 F/ A/ G/ F/ E/ D/ C/ C/ || %8  