Construct a musical composition that imitates the elements typically found in Bach's works.  
X:1
T:Music21 Fragment
T:Music21 Fragment
T:Music21
C:Music21
%%score 1 2 3 4
L:1/4
M:4/4
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 bass 
%%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
 z3 C/D/ | E F G G | A B !fermata!c C/D/ | E F G G | F E !fermata!D E | C C F E | %6
 D2 !fermata!C C/D/ | E F G G | A B !fermata!c C/D/ | E F G G | F E !fermata!D E | C C F E | %12
 D2 !fermata!C G | D E F F | E E !fermata!D G | A B c E | D D !fermata!C z |] %17
V:2
 z3 G, | C B, C E | F/E/ D !fermata!E G, | C D2 C | C/B,/ C !fermata!B, B, | B, A, A,/B,/ C | %6
 C B, !fermata!G, G, | C B, C E | F/E/ D !fermata!E G, | C D2 C | C/B,/ C !fermata!B, B, | %11
 B, A, A,/B,/ C | C B, !fermata!G, C | D D ^C D | D ^C !fermata!A, =C | C G/F/ E/D/ C | %16
 C B, !fermata!G, z |] %17
V:3
 z3 E,/F,/ | G, F, E,/G,/ C | C G, !fermata!G, E, | A, A, G,/F,/ E, | F, G, !fermata!G, E, | %5
 E, E, D, E, | A, G,/F,/ !fermata!E, E,/F,/ | G, F, E,/G,/ C | C G, !fermata!G, E, | %9
 A, A, G,/F,/ E, | F, G, !fermata!G, E, | E, E, D, E, | A, G,/F,/ !fermata!E, E, | F, G, A, =B, | %14
 E,/F,/ G, !fermata!F, G, | F,/E,/ D, C,/D,/ E,/F,/ | G,/D,/ G,/F,/ !fermata!E, z |] %17
V:4
 z3"C" C, |"C" C,"Bdim/D" D,"C/E" E,"C" C, |"F" F,"G" G,"C" !fermata!C,"C" C,/B,,/ | %3
"Am" A,,"Dm/G" G,,/F,,/"Em" E,,"Am7" A,, |"Dm" D,,"C/E" E,,/F,,/"G" !fermata!G,,"E/G#" ^G,, | %5
"Am" A,,/B,,/"Am/C" C,/A,,/"Dm" D,"Am" A,,/G,,/ |"Dm7/F" F,,"G" G,,"C" !fermata!C,,"C" C, | %7
"C" C,"Bdim/D" D,"C/E" E,"C" C, |"F" F,"G" G,"C" !fermata!C,"C" C,/B,,/ | %9
"Am" A,,"Dm/G" G,,/F,,/"Em" E,,"Am7" A,, |"Dm" D,,"C/E" E,,/F,,/"G" !fermata!G,,"E/G#" ^G,, | %11
"Am" A,,/B,,/"Am/C" C,/A,,/"Dm" D,"Am" A,,/G,,/ |"Dm7/F" F,,"G" G,,"C" !fermata!C,,"C" C, | %13
"Bdim" B,,"Em7b5/Bb" _B,,"F+/A" A,,"G#dim7" ^G,, |"Asus4" A,,"A7" A,,"Dm" !fermata!D,,"C/E" E,, | %15
"F" F,,"G" G,,"Am" A,,/B,,/"C" C, |"Gsus4" G,,"G" G,,"C" !fermata!C,, z |] %17  