Printing RGB-colored text in xterm/gnome-terminal using Python

color_string.py

def color_string(str, foreground=None, background=None):
    reset = '\033[0m'
    if foreground:
        assert len(foreground) == 3, "Foreground color needs to be a collection of 3 integer values"
        R, G, B = int(foreground[0]), int(foreground[1]), int(foreground[2])
        foreground = '\033[38;2;{R};{G};{B}m'.format(R=R, G=G, B=B)
    else:
        foreground = ''
    if background:
        assert len(background) == 3, "Background color needs to be a collection of 3 integer values"
        R, G, B = int(background[0]), int(background[1]), int(background[2])
        background = '\033[48;2;{R};{G};{B}m'.format(R=R, G=G, B=B)
    else:
        background = ''
    return ''.join([foreground, background, str, reset])

# Print blue text on bright orange background
print(color_string('stuff', (0,0,255), (255,131,0)))