old_contents: __version__ = '0.1.0'
  
  from dnszone import ForwardZone, ReverseZone
  from dnsrecord import SOA, NS, A, AAAA, CNAME, MX, TXT, PTR
  from bindconf import BINDConf, ACL, Masters, View, Zone
  
new_contents: __version__ = '0.1.0'
  
  from dnszone import ForwardZone, ReverseZone
  from dnsrecord import SOA, NS, A, AAAA, CNAME, MX, TXT, PTR
  from bindconf import BINDConf, ACL, Masters, NamedMasters, View, Zone
  
subject: add NamedMasters to __init__.py