code: def get_rdataset(self, name, rdtype, covers=dns.rdatatype.NONE,
                       create=False):
          
  
          try:
              rdataset = self.find_rdataset(name, rdtype, covers, create)
          except KeyError:
              rdataset = None
          return rdataset
docs: Look for rdata with the specified name and type in the zone,
          and return an rdataset encapsulating it.
  
          The I{name}, I{rdtype}, and I{covers} parameters may be
          strings, in which case they will be converted to their proper
          type.
  
          The rdataset returned is not a copy; changes to it will change
          the zone.
  
          None is returned if the name or type are not found.
          Use L{find_rdataset} if you want to have KeyError raised instead.
  
          @param name: the owner name to look for
          @type name: DNS.name.Name object or string
          @param rdtype: the rdata type desired
          @type rdtype: int or string
          @param covers: the covered type (defaults to None)
          @type covers: int or string
          @param create: should the node and rdataset be created if they do not
          exist?
          @type create: bool
          @rtype: dns.rrset.RRset object