use Term::ExtendedColor::Xresources qw(
  get_xterm_color
  set_xterm_color
  set_foreground_color
  set_background_color
);

# make color index 220 represent red instead of yellow
set_xterm_color({ 220 => 'ff0000'});

# get RGB values for all defined colors
my $colors = get_xterm_color({
  index => [0 .. 255], # default
  type  => 'hex',      # default is base 10
});

# change the background color to red...
set_background_color('ff0000');

# .. and the foreground color to yellow
set_foreground_color('ffff00');