new_contents: #!/usr/bin/env python3
  
  import socket
  
  import dns.flags
  import dns.message
  import dns.rdataclass
  import dns.rdatatype
  
  address = '127.0.0.1'
  port = 53535
  
  s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
  s.bind((address, port))
  while True:
      (wire, address) = s.recvfrom(512)
      notify = dns.message.from_wire(wire)
      soa = notify.find_rrset(notify.answer, notify.question[0].name,
                              dns.rdataclass.IN, dns.rdatatype.SOA)
  
      # Do something with the SOA RR here
      print('The serial number for', soa.name, 'is', soa[0].serial)
  
      response = dns.message.make_response(notify)
      response.flags |= dns.flags.AA
      wire = response.to_wire(response)
      s.sendto(wire, address)
  
subject: add example of receiving notify messages