old_contents: """
  docstring
  """
  
  __version__ = '$Revision$'
  # $Source$
  
  from dnszone import ForwardZone, ReverseZone
  from dnsrecord import SOA, NS, A, AAAA, CNAME, MX, TXT PTR
  from bindconf import BINDConf, ACL, View, Zone
  
new_contents: """
  docstring
  """
  
  __version__ = '$Revision$'
  # $Source$
  
  from dnszone import ForwardZone, ReverseZone
  from dnsrecord import SOA, NS, A, AAAA, CNAME, MX, TXT, PTR
  from bindconf import BINDConf, ACL, View, Zone
  
subject: correct syntax