code: def _get_match(self, host_object):
          
          i = self._get_insertion_point(host_object)
          potential_match = None
          try:
              potential_match = self[i-1]
          except IndexError:
              pass
  
          if host_object.is_match(potential_match):
              return potential_match
          return None
docs: Get an item matching the given host object.
  
          The item may be either a parent domain or identical value.
          Parent domains and existing identical values always precede
          insertion point for given value - therefore, we treat
          an item just before insertion point as potential match.
  
          :param host_object: an object representing ip address
          or hostname whose match we are trying to find