New in version 2.0.
Color note:
abjad> note = Note("c'4")
abjad> leaftools.color_leaf(note, 'red')
Note("c'4")
abjad> f(note)
\once \override Accidental #'color = #red
\once \override Dots #'color = #red
\once \override NoteHead #'color = #red
c'4
Color rest:
abjad> rest = Rest('r4')
abjad> leaftools.color_leaf(rest, 'red')
Rest('r4')
abjad> f(rest)
\once \override Dots #'color = #red
\once \override Rest #'color = #red
r4
Color chord:
abjad> chord = Chord("<c' e' bf'>4")
abjad> leaftools.color_leaf(chord, 'red')
Chord("<c' e' bf'>4")
abjad> f(chord)
\once \override Accidental #'color = #red
\once \override Dots #'color = #red
\once \override NoteHead #'color = #red
<c' e' bf'>4
Return leaf.