new_contents: import os
  import sys
  import struct
  import unittest
  import platform
  from   ctypes import *
  from   nose.tools import ok_, eq_, raises
  from   capper._libpcap import (
      load_libpcap,
      setup_libpcap,
  )
  
  
  class TestLibpcap(unittest.TestCase):
      def setUp(self):
          pass
  
      def test_load_libpcap(self):
          pcap = load_libpcap()
          ok_(pcap.pcap_lib_version(None))
  
      def tearDown(self):
          pass
  
  
subject: add _libpcap tests