How to use the desert.color.black function in desert

def main(arg):

  with Desert(1000, show=True, verbose=VERBOSE)\
      .init(fg=black(0.001),
            bg=white()) as c:

    density = 0.15
    num = 20
    rad = 0.35

    noise = 0.00005
    spl = []

    for _ in range(20):
      a = sorted(random(num)*TWOPI)
      spl.append(0.5 + column_stack((cos(a), sin(a)))*rad)

    res = []
    for i in range(1, 4000000):
      for xy in spl:

def main(arg):

  with Desert(1000, show=True, verbose=VERBOSE)\
      .init(fg=black(0.001),
            bg=white()) as c:

    density = 0.02
    a = random(2)*TWOPI
    acc = zeros(2)
    noise = 0.000000005
    rad = 0.45

    resa = []
    resb = []

    for i in range(4000000):
      a += acc
      acc += (1-2*random(2))*noise

      resa.append((cos(a[0]), sin(a[0])))

(0.1, 0.9),
              (0.9, 0.9),
              (0.2, 0.15)), 2).rgb(black(0.4)).json()

  pprint(s)
  pprint(stroke.from_json(s).json())
  pprint()

  c = circle(0.05, ((0.5, 0.4), (0.8, 0.4)), 1.0).json()
  pprint(c)
  pprint(circle.from_json(c).json())
  pprint()

  c = circle(0.05, ((0.5, 0.4), (0.8, 0.4)), 1.0)\
      .rgb([
          black(0.3),
          black(0.1)]).json()
  pprint(c)
  pprint(circle.from_json(c).json())
  pprint()

  r = rgb(0.1, 0.4, 0.3, 0.99).json()
  pprint(r)
  pprint(Rgba.from_json(r).json())
  pprint()

  b = bzspl([[(0.1, 0.2),
              (0.4, 0.25),
              (0.9, 0.15),
              (0.9, 0.3),
              (0.95, 0.45),
              (0.8, 0.9)]], 2, closed=True).json()

def main():

  b = box(0.3, (0.3, 0.3), 1.0).rgb(rgb(0.1, 0.3, 0.4, 0.77)).json()
  pprint(b)
  pprint(box.from_json(b).json())
  pprint()

  s = stroke(((0.1, 0.1),
              (0.1, 0.1),
              (0.1, 0.9),
              (0.1, 0.1)),
             ((0.9, 0.9),
              (0.1, 0.9),
              (0.9, 0.9),
              (0.2, 0.15)), 2).rgb(black(0.4)).json()

  pprint(s)
  pprint(stroke.from_json(s).json())
  pprint()

  c = circle(0.05, ((0.5, 0.4), (0.8, 0.4)), 1.0).json()
  pprint(c)
  pprint(circle.from_json(c).json())
  pprint()

  c = circle(0.05, ((0.5, 0.4), (0.8, 0.4)), 1.0)\
      .rgb([
          black(0.3),
          black(0.1)]).json()
  pprint(c)
  pprint(circle.from_json(c).json())

(0.9, 0.9),
              (0.2, 0.15)), 2).rgb(black(0.4)).json()

  pprint(s)
  pprint(stroke.from_json(s).json())
  pprint()

  c = circle(0.05, ((0.5, 0.4), (0.8, 0.4)), 1.0).json()
  pprint(c)
  pprint(circle.from_json(c).json())
  pprint()

  c = circle(0.05, ((0.5, 0.4), (0.8, 0.4)), 1.0)\
      .rgb([
          black(0.3),
          black(0.1)]).json()
  pprint(c)
  pprint(circle.from_json(c).json())
  pprint()

  r = rgb(0.1, 0.4, 0.3, 0.99).json()
  pprint(r)
  pprint(Rgba.from_json(r).json())
  pprint()

  b = bzspl([[(0.1, 0.2),
              (0.4, 0.25),
              (0.9, 0.15),
              (0.9, 0.3),
              (0.95, 0.45),
              (0.8, 0.9)]], 2, closed=True).json()

draw([circle(0.05, ((0.9, 0.1),
                        (0.9, 0.15),
                        (0.9, 0.2),
                        (0.9, 0.25),
                        (0.9, 0.3)), 2)\
          .rgb([rgb(0.2, 0.2, 0.9, 0.3),
                rgb(0.9, 0.2, 0.2, 0.3),
                rgb(0.2, 0.9, 0.2, 0.3),
                rgb(0.9, 0.9, 0.2, 0.3),
                rgb(0.2, 0.9, 0.9, 0.3)]),
          circle(0.05, ((0.85, 0.1),
                        (0.85, 0.3)), 2)\
          .rgb([rgb(0.5, 0.2, 0.9, 0.3),
                rgb(0.9, 0.5, 0.2, 0.3)])]).show()

    desert.set_fg(black())

    draw([bzspl([[(0.1, 0.2),
                  (0.3, 0.4),
                  (0.5, 0.6)],
                 [(0.15, 0.25),
                  (0.35, 0.45),
                  (0.55, 0.65)]], 2)]).show()

    draw([bzspl([[(0.1, 0.2),
                  (0.8, 0.3),
                  (0.3, 0.9)]], 2)]).show()

    draw([bzspl([[(0.1, 0.2),
                  (0.8, 0.3),
                  (0.3, 0.9)],
                 [(0.35, 0.25),

send([circle(0.05, ((0.9, 0.1),
                        (0.9, 0.15),
                        (0.9, 0.2),
                        (0.9, 0.25),
                        (0.9, 0.3)), 2)\
          .rgb([rgb(0.2, 0.2, 0.9, 0.3),
                rgb(0.9, 0.2, 0.2, 0.3),
                rgb(0.2, 0.9, 0.2, 0.3),
                rgb(0.9, 0.9, 0.2, 0.3),
                rgb(0.2, 0.9, 0.9, 0.3)]),
          circle(0.05, ((0.85, 0.1),
                        (0.85, 0.3)), 2)\
          .rgb([rgb(0.5, 0.2, 0.9, 0.3),
                rgb(0.9, 0.5, 0.2, 0.3)])])

    erosion.set_fg(black())

    send([bzspl([[(0.1, 0.2),
                  (0.3, 0.4),
                  (0.5, 0.6)],
                 [(0.15, 0.25),
                  (0.35, 0.45),
                  (0.55, 0.65)]], 2)])

    send([bzspl([[(0.1, 0.2),
                  (0.8, 0.3),
                  (0.3, 0.9)]], 2)])

    send([bzspl([[(0.1, 0.2),
                  (0.8, 0.3),
                  (0.3, 0.9)],
                 [(0.35, 0.25),