Use print function

examples/multiping.py

@@ -8,6 +8,8 @@ multiple hosts and monitor their output interactively for a period=
 of time.
 """
 
+from __future__ import print_function
+
 from mininet.net import Mininet
 from mininet.node import Node
 from mininet.topo import SingleSwitchTopo
@@ -34,7 +36,7 @@ def startpings( host, targetips ):
             ' done; '
             'done &' )
 
-    print ( '*** Host %s (%s) will be pinging ips: %s' %
+    print( '*** Host %s (%s) will be pinging ips: %s' %
             ( host.name, host.IP(), targetips ) )
 
     host.cmd( cmd )
@@ -69,7 +71,7 @@ def multiping( netsize, chunksize, seconds):
         readable = poller.poll(1000)
         for fd, _mask in readable:
             node = Node.outToNode[ fd ]
-            print '%s:' % node.name, node.monitor().strip()
+            print( '%s:' % node.name, node.monitor().strip() )
 
     # Stop pings
     for host in hosts: