Develop a musical melody with elements from Bach's compositions.  
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
L:1/8
V:1
 E E ^F ^G | A2 !fermata!^G2 | ^G G A B | c2 !fermata!B2 | c c B B | A2 !fermata!^G2 | A A G G | %7
 F2 !fermata!E2 | e e d d | c2 !fermata!B2 | A A G G | F2 !fermata!E2 |] %12
V:2
 B, C D D | E D !fermata!E2 | E E E/^F/ ^G | A2 A !fermata!^G | =G/^F/ G/A/ G =F | %5
 E ^F !fermata!E2 | C F/E/ D/C/ D/E/ | D2 !fermata!C2 | G G G G/F/ | E2 !fermata!E2 | C F F E | %11
 E D/C/ !fermata!B,2 |] %12
V:3
 G, A,/^G,/ A, B, | C B,/A,/ !fermata!B,2 | B, B, C D | E2 !fermata!E2 | E3/2 D/ D D | %5
 D/ C B,/ !fermata!B,2 | A,/G,/ F, G, D,/A,/ | A, G, !fermata!G,2 | C C2 B, | B, A,2 !fermata!^G, | %10
 A,/B,/ C C C/_B,/ | A,/C/ =B,/A,/ !fermata!^G,2 |] %12
V:4
"Em" E,D,"Am/C" C,2"D7/C" C,D,"G#dim/C" C,B,, |"Am" A,,G,,"Bm7b5/F" F,,2"E" !fermata!E,,4 | %2
"E7/D" D,F,"E" E,D,"Am/C" C,D,"G#dim/C" C,B,, |"Am" A,,B,,"Am/C" C,D,"Esus4" !fermata!E,4 | %4
"C/E" E,D,"C/E" E,^F,"G" G,F,"G7" G,^G, |"Asus4" A,2"D#dim7" ^D,2"E" !fermata!E,4 | %6
"F" =F,E,"Dm" D,C,"G/B" B,,A,,"G/B" B,,^C, |"Dm" D,C,"G7/B" B,,G,,"C" !fermata!C,4 | %8
"C" C,D,"C/E" E,F,"Gsus4" G,A,"G/B" B,G, |"Am" A,,B,,"Am/C" C,D,"E" !fermata!E,4 | %10
"F" F,,G,,"F/A" A,,B,,"Csus4" C,D,"C/E" E,C, |"Dm9" D,4"E" !fermata!E,4 |] %12  