Run MiniEdit, find and open 10_7_sdn_miniedit.mn, which will create a visual representation of the Python program of listing 10.7 listed as follows:

#!/usr/bin/env python 
# Python Network Programming Cookbook, Second Edition -- Chapter - 10 
# This program is optimized for Python 2.7.12. 
# It may run on any other version with/without modifications. 
 
from mininet.net import Mininet 
from mininet.node import Controller, RemoteController, OVSController 
from mininet.node import CPULimitedHost, Host, Node 
from mininet.node import OVSKernelSwitch, UserSwitch 
from mininet.node import IVSSwitch 
from mininet.cli import CLI 
from mininet.log import setLogLevel, info 
from mininet.link import TCLink, Intf 
from subprocess import call 
 
def myNetwork(): 
 
    net = Mininet( topo=None, 
                   build=False, 
                   ipBase='10.0.0.0/8') 
 
    info( '*** Adding controller
' ) 
    c0=net.addController(name='c0', 
                      controller=Controller, 
                      protocol='tcp', 
                      port=6633) 
 
    info( '*** Add switches
') 
    s9 = net.addSwitch('s9', cls=OVSKernelSwitch) 
    s8 = net.addSwitch('s8', cls=OVSKernelSwitch) 
    s4 = net.addSwitch('s4', cls=OVSKernelSwitch) 
    s5 = net.addSwitch('s5', cls=OVSKernelSwitch) 
    s7 = net.addSwitch('s7', cls=OVSKernelSwitch) 
    s6 = net.addSwitch('s6', cls=OVSKernelSwitch) 
    s10 = net.addSwitch('s10', cls=OVSKernelSwitch) 
    s1 = net.addSwitch('s1', cls=OVSKernelSwitch) 
    s3 = net.addSwitch('s3', cls=OVSKernelSwitch) 
    s2 = net.addSwitch('s2', cls=OVSKernelSwitch) 
 
    info( '*** Add hosts
') 
    h3 = net.addHost('h3', cls=Host, ip='10.0.0.3', defaultRoute=None) 
    h9 = net.addHost('h9', cls=Host, ip='10.0.0.9', defaultRoute=None) 
    h1 = net.addHost('h1', cls=Host, ip='10.0.0.1', defaultRoute=None) 
    h7 = net.addHost('h7', cls=Host, ip='10.0.0.7', defaultRoute=None) 
    h10 = net.addHost('h10', cls=Host, ip='10.0.0.10', defaultRoute=None) 
    h2 = net.addHost('h2', cls=Host, ip='10.0.0.2', defaultRoute=None) 
    h6 = net.addHost('h6', cls=Host, ip='10.0.0.6', defaultRoute=None) 
    h4 = net.addHost('h4', cls=Host, ip='10.0.0.4', defaultRoute=None) 
    h11 = net.addHost('h11', cls=Host, ip='10.0.0.11', defaultRoute=None) 
    h8 = net.addHost('h8', cls=Host, ip='10.0.0.8', defaultRoute=None) 
    h5 = net.addHost('h5', cls=Host, ip='10.0.0.5', defaultRoute=None) 
 
    info( '*** Add links
') 
    s7s1 = {'bw':250,'loss':0} 
    net.addLink(s7, s1, cls=TCLink , **s7s1) 
    s7s8 = {'bw':250,'loss':0} 
    net.addLink(s7, s8, cls=TCLink , **s7s8) 
    s8s2 = {'bw':250,'loss':0} 
    net.addLink(s8, s2, cls=TCLink , **s8s2) 
    net.addLink(s1, s3) 
    net.addLink(s1, s4) 
    net.addLink(s1, s9) 
    net.addLink(s1, s10) 
    net.addLink(s1, s5) 
    net.addLink(s1, s6) 
    net.addLink(s2, s3) 
    net.addLink(s2, s4) 
    net.addLink(s2, s9) 
    net.addLink(s2, s10) 
    net.addLink(s2, s5) 
    net.addLink(s2, s6) 
    net.addLink(s3, h1) 
    net.addLink(s3, h2) 
    net.addLink(s4, h3) 
    net.addLink(s4, h4) 
    net.addLink(s9, h5) 
    net.addLink(s9, h6) 
    net.addLink(s10, h7) 
    net.addLink(s10, h8) 
    net.addLink(s5, h9) 
    net.addLink(s6, h10) 
    net.addLink(s6, h11) 
 
    info( '*** Starting network
') 
    net.build() 
    info( '*** Starting controllers
') 
    for controller in net.controllers: 
        controller.start() 
 
    info( '*** Starting switches
') 
    net.get('s9').start([]) 
    net.get('s8').start([c0]) 
    net.get('s4').start([]) 
    net.get('s5').start([]) 
    net.get('s7').start([c0]) 
    net.get('s6').start([]) 
    net.get('s10').start([]) 
    net.get('s1').start([]) 
    net.get('s3').start([]) 
    net.get('s2').start([]) 
 
    info( '*** Post configure switches and hosts
') 
 
    CLI(net) 
    net.stop() 
 
if __name__ == '__main__': 
    setLogLevel( 'info' ) 
    myNetwork() 

Running this recipe will produce the following output:

$ sudo python 10_7_sdn_miniedit.py 
*** Adding controller
*** Add switches
*** Add hosts
*** Add links
(250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) *** Starting network
*** Configuring hosts
*** Starting controllers
*** Starting switches
(250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) (250.00Mbit 0.00000% loss) *** Post configure switches and hosts
*** Starting CLI:

Opening and running 10_7_sdn_miniedit.mn will produce the same output as the preceding recipe, since both the .mn and .py files of this recipe were originally exported from the same network designed using MiniEdit. The following screenshot indicates the network topology emulated by the preceding recipe as opened from the .mn file, along with its execution output: