old_contents: # encoding: utf-8
  
  """
  .. codeauthor:: Tsuyoshi Hombashi <tsuyoshi.hombashi@gmail.com>
  """
  
  from __future__ import absolute_import
  from __future__ import division
  
  import abc
  
  
  class PingParserInterface(object):
  
      @abc.abstractproperty
      def packet_transmit(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_receive(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_loss_rate(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_loss_count(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def rtt_min(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def rtt_avg(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def rtt_max(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def rtt_mdev(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_duplicate_rate(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_duplicate_count(self):  # pragma: no cover
          pass
  
new_contents: # encoding: utf-8
  
  """
  .. codeauthor:: Tsuyoshi Hombashi <tsuyoshi.hombashi@gmail.com>
  """
  
  from __future__ import absolute_import
  from __future__ import division
  
  import abc
  
  import six
  
  
  @six.add_metaclass(abc.ABCMeta)
  class PingParserInterface(object):
  
      @abc.abstractproperty
      def packet_transmit(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_receive(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_loss_rate(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_loss_count(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def rtt_min(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def rtt_avg(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def rtt_max(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def rtt_mdev(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_duplicate_rate(self):  # pragma: no cover
          pass
  
      @abc.abstractproperty
      def packet_duplicate_count(self):  # pragma: no cover
          pass
  
subject: Fix missing metaclass for an interface class