text: from django.test import TestCase
  
  from storage.models import PhoneModel
  
  
  class PhoneModelModelTest(TestCase):
  
      @classmethod
      def setUpTestData(cls):
          cls.phone_model = PhoneModel.objects.create(name='Big', brand='Bob', model_year=1997)
  
      def test_fields_max_length(self):
          max_length_name = self.phone_model._meta.get_field('name').max_length
          max_length_brand = self.phone_model._meta.get_field('brand').max_length
          self.assertEquals(max_length_name, 200)
          self.assertEquals(max_length_brand, 30)
  