def mandelbrot(c,maxiter):
z = c
for n in range(maxiter):
    if abs(z) > 2:
        return n
    z = z*z + c
return 0

def julia (c,maxiter):
z = 0
c = complex(-0.1, 0.65)
for n in range(maxiter):
    if abs(z) > 2:
        return n
    z = z*z + c
return 0

def julia_set(xmin,xmax,ymin,ymax,width,height,maxiter):
r1 = np.linspace(xmin, xmax, width)
r2 = np.linspace(ymin, ymax, height)
n3 = np.empty((width,height))
for i in range(width):
    for j in range(height):
        n3[i,j] = julia(r1[i] + 1j*r2[j],maxiter)
return (r1,r2,n3)

from matplotlib import pyplot as plt
from matplotlib import colors
%matplotlib inline

def julia_image(xmin,xmax,ymin,ymax,width=10,height=10,maxiter=100,cmap='hot'):
dpi = 50
img_width = dpi * width
img_height = dpi * height
x,y,z = julia_set(xmin,xmax,ymin,ymax,img_width,img_height,maxiter)

fig, ax = plt.subplots(figsize=(width, height),dpi=50)
ticks = np.arange(0,img_width,3*dpi)
x_ticks = xmin + (xmax-xmin)*ticks/img_width
plt.xticks(ticks, x_ticks)
y_ticks = ymin + (ymax-ymin)*ticks/img_width
plt.yticks(ticks, y_ticks)

ax.imshow(z.T,cmap=cmap,origin='lower')

julia_image(-2.0,2.0,-3,3,cmap='afmhot')