text: import unittest
  
  from . import mixin
  
  
  class IotApiTest(mixin.AioMixin, unittest.IsolatedAsyncioTestCase):
      async def test_01(self):
          resp = await self.api.device_update()
          self.assertEqual(resp.status, 400)
  
      async def test_02(self):
          json = '{"tag":"test-tag"}'
          resp = await self.api.device_update(json=json)
          self.assertEqual(resp.status, 400)
          x = await resp.json()
          msg = await resp.text()
          try:
              self.assertEqual(
                  x['validations']['body'][0]['property'],
                  'instance.deviceidlist', msg)
          except KeyError as e:
              self.fail('KeyError %s: %s' % (e, msg))
  