old_contents: from corehq.apps.domain.shortcuts import create_domain
  from django.test import TestCase
  from django.test.client import RequestFactory
  
  from corehq.apps.users.models import WebUser
  
  from ..interface import EnterpriseSMSBillablesInterface
  
  
  class TestEnterpriseSMSBillablesInterface(TestCase):
  
      @classmethod
      def setUpClass(cls):
          cls.domain = 'test-domain'
          cls.domain_obj = create_domain(cls.domain)
  
      @classmethod
      def tearDownClass(cls):
          cls.domain_obj.delete()
  
      def test_headers(self):
          interface = self.create_interface()
          test_headers = [['Date of Message', 'Project Space', 'Direction', 'SMS parts', 'Gateway',
              'Gateway Charge', 'Usage Charge', 'Total Charge', 'Message Log ID', 'Is Valid?', 'Date Created']]
          self.assertEqual(interface.headers.as_export_table, test_headers)
  
      def create_interface(self):
          request = RequestFactory().get('')
          user = WebUser()
          request.couch_user = user
          return EnterpriseSMSBillablesInterface(request)
  
new_contents: from corehq.apps.domain.shortcuts import create_domain
  from django.test import TestCase
  from django.test.client import RequestFactory
  
  from corehq.apps.users.models import WebUser
  
  from ..interface import EnterpriseSMSBillablesInterface
  
  
  class TestEnterpriseSMSBillablesInterface(TestCase):
  
      def test_headers(self):
          interface = self.create_interface()
          test_headers = [['Date of Message', 'Project Space', 'Direction', 'SMS parts', 'Gateway',
              'Gateway Charge', 'Usage Charge', 'Total Charge', 'Message Log ID', 'Is Valid?', 'Date Created']]
          self.assertEqual(interface.headers.as_export_table, test_headers)
  
      def create_interface(self):
          request = RequestFactory().get('')
          user = WebUser()
          request.couch_user = user
          return EnterpriseSMSBillablesInterface(request)
  
subject: remove useless code in test