new_contents: import unittest
  import mock
  from ..device_credentials import DeviceCredentials
  
  
  class TestDeviceCredentials(unittest.TestCase):
  
      @mock.patch('auth0.v2.device_credentials.RestClient')
      def test_get(self, mock_rc):
          mock_instance = mock_rc.return_value
  
          c = DeviceCredentials(domain='domain', jwt_token='jwttoken')
          c.get(user_id='uid', client_id='cid', type='type')
  
          args, kwargs = mock_instance.get.call_args
  
          self.assertEqual('https://domain/api/v2/device-credentials', args[0])
          self.assertEqual(kwargs['params'], {'fields': None,
                                              'include_fields': 'true',
                                              'user_id': 'uid',
                                              'client_id': 'cid',
                                              'type': 'type'})
  
      @mock.patch('auth0.v2.device_credentials.RestClient')
      def test_create(self, mock_rc):
          mock_instance = mock_rc.return_value
  
          c = DeviceCredentials(domain='domain', jwt_token='jwttoken')
          c.create({'a': 'b', 'c': 'd'})
  
          args, kwargs = mock_instance.post.call_args
  
          self.assertEqual('https://domain/api/v2/device-credentials', args[0])
          self.assertEqual(kwargs['data'], {'a': 'b', 'c': 'd'})
  
      @mock.patch('auth0.v2.device_credentials.RestClient')
      def test_delete(self, mock_rc):
          mock_instance = mock_rc.return_value
  
          c = DeviceCredentials(domain='domain', jwt_token='jwttoken')
          c.delete('an-id')
  
          mock_instance.delete.assert_called_with(
              'https://domain/api/v2/device-credentials/an-id',
          )
  
subject: Add unit tests for DeviceCredentials