List all the ports opened by processes on the local machine

ports_per_processes.py

#!/usr/bin/python
import psutil

"""
List all the ports opened by processes on the local machine
to run it with sudo: sudo python port_processes.py
"""

connections = {}
for c in psutil.net_connections():
    if c.status == 'LISTEN':
        connections[c.pid] = connections.get(c.pid, set())
        connections[c.pid].add(c.laddr[1])

for k, v in connections.iteritems():
    p = psutil.Process(k)
    print("Process:", p.name(), "Dir:", p.cwd(), "Ports:", list(v))

how do I list the ports that are being used for each PID?