old_contents: 
  from nose.tools import with_setup, raises
  from urllib2 import URLError
  from wsgi_intercept.mechanize_intercept import Browser
  import wsgi_intercept
  from wsgi_intercept import test_wsgi_app
  from mechanize import Browser as MechanizeBrowser
  
  ###
  
  _saved_debuglevel = None
  
  def add_intercept():
      # _saved_debuglevel, wsgi_intercept.debuglevel = wsgi_intercept.debuglevel, 1
      wsgi_intercept.add_wsgi_intercept('some_hopefully_nonexistant_domain', 80, test_wsgi_app.create_fn)
      
  def add_https_intercept():
      wsgi_intercept.add_wsgi_intercept('some_hopefully_nonexistant_domain', 443, test_wsgi_app.create_fn)
  
  def remove_intercept():
      wsgi_intercept.remove_wsgi_intercept('some_hopefully_nonexistant_domain', 80)
      # wsgi_intercept.debuglevel = _saved_debuglevel
  
  @with_setup(add_intercept, remove_intercept)
  def test_intercepted():
      b = Browser()
      b.open('http://some_hopefully_nonexistant_domain:80/')
      assert test_wsgi_app.success()
  
  @with_setup(add_intercept)
  @raises(URLError)
  def test_intercept_removed():
      remove_intercept()
      b = Browser()
      b.open('http://some_hopefully_nonexistant_domain:80/')
  
  @with_setup(add_https_intercept, remove_intercept)
  def test_https_intercept():
      b = Browser()
      b.open('https://some_hopefully_nonexistant_domain:443/')
      assert test_wsgi_app.success()
  
  @with_setup(add_intercept, remove_intercept)
  def test_https_intercept_default_port():
      b = Browser()
      b.open('https://some_hopefully_nonexistant_domain/')
      assert test_wsgi_app.success()
new_contents: from urllib2 import URLError
  from wsgi_intercept import testing
  from wsgi_intercept.testing import unittest
  from wsgi_intercept.test import base
  
  try:
      import mechanize
      has_mechanize = True
  except ImportError:
      has_mechanize = False
  _skip_message = "mechanize is not installed"
  
  
  @unittest.skipUnless(has_mechanize, _skip_message)
  class MechanizeHttpTestCase(base.BaseTestCase):
      port = 80
  
      def make_one(self, *args):
          from mechanize import Browser
          return Browser(*args)
  
      def test_intercepted(self):
          b = self.make_one()
          b.open(self.url)
          self.assertTrue(testing.success())
  
      def test_intercept_removed():
          remove_intercept()
          b = self.make_one()
          with self.assertRaises(URLError):
              b.open(self.url)
  
  
  @unittest.skipUnless(has_mechanize, _skip_message)
  class MechanizeHttpsTestCase(MechanizeHttpTestCase):
      port = 443
  
subject: Use unittest in the mechanize related tests.