Create a composition emulating Bach's signature style.  
X:1
T:Music21 Fragment
T:Music21 Fragment
T:Music21
C:Music21
%%score 1 2 3 4
L:1/4
M:3/4
K:C
V:1 treble 
%%MIDI program 0
%%MIDI control 7 100
%%MIDI control 10 64
V:2 treble 
%%MIDI program 0
%%MIDI control 7 100
%%MIDI control 10 64
V:3 treble 
%%MIDI program 0
%%MIDI control 7 100
%%MIDI control 10 64
V:4 bass 
%%MIDI program 0
%%MIDI control 7 100
%%MIDI control 10 64
V:1
 c c g | e3/2 d/ c | B c/B/ A/G/ | c d e/f/ | d2 !fermata!c | c c g | e3/2 d/ c | B c/B/ A/G/ | %8
 c d e/f/ | d2 !fermata!c | g f/e/ d/c/ | !fermata!a2 z | e f g | g a/g/ f/e/ | !fermata!d2 z | %15
 G A B | c d e/f/ | d2 !fermata!c |] %18
V:2
 G G G | G3/2 G/ A | D D D | G A/B/ c/d/ | B2 !fermata!G | G G G | G3/2 G/ A | D D D | %8
 G A/B/ c/d/ | B2 !fermata!G | c B G | !fermata!c2 z | c c B/A/ | G c A | !fermata!B2 z | G D D | %16
 C G G | G3/2 F/ !fermata!E |] %18
V:3
 E E D | C3/2 D/ E/^F/ | G G B, | C F, G, | G F !fermata!E | E E D | C3/2 D/ E/^F/ | G G B, | %8
 C F, G, | G F !fermata!E | E F G | !fermata!F2 z | G A D | D C C | !fermata!G2 z | C B,/A,/ =F | %16
 E D C | C B, !fermata!G, |] %18
V:4
"C" C"C" C"G/B" B, |"C" C3/2 B,/"Am" A, |"G" G,"G" D,"Bm7b5/F" F, |"C/E" E,"Dm" D,"C" C, | %4
"G7" G,2"C" !fermata!C, |"C" C"C" C"G/B" B, |"C" C3/2 B,/"Am" A, |"G" G,"G" D,"Bm7b5/F" F, | %8
"C/E" E,"Dm" D,"C" C, |"G7" G,2"C" !fermata!C, |"C" C,"Bdim/D" D,"Em" E, |"F" !fermata!F,2 z | %12
"C" C"F/B" B,/A,/"G" G,/F,/ |"Em" E,"Am/E" E,"F" F, |"G" !fermata!G,2 z | %15
"C/E" E,"Bm7/F#" ^F,"G#dim7" ^G, |"Am" A,"G/B" B,"C" C |"Gsus4" G,2"C" !fermata!C, |] %18  