old_contents: """Unit test the farms models."""
  
  from farms.factories import AddressFactory
  
  from mock import MagicMock
  
  
  def test_address_factory_generates_valid_addresses_sort_of(mocker):
      """Same test, but using pytest-mock."""
      mocker.patch('farms.models.Address.save', MagicMock(name="save"))
  
      address = AddressFactory.create()
  
      assert address.street is not ''
      assert address.postal_code is not ''
      assert len(address.postal_code) == 5
      assert address.city is not ''
  
new_contents: """Unit test the farms models."""
  
  from ..factories import AddressFactory
  from ..models import Address
  
  import pytest
  
  
  def test_address_factory_generates_valid_address():
      # GIVEN any state
      # WHEN building a new address
      address = AddressFactory.build()
  
      # THEN it has all the information we want
      assert address.street is not ''
      assert address.postal_code is not ''
      assert len(address.postal_code) == 5
      assert address.city is not ''
  
  
  @pytest.mark.django_db
  def test_address_can_be_saved_and_retrieved():
      # GIVEN a fresh address instance
      address = AddressFactory.build()
      street = address.street
      postal_code = address.postal_code
  
      # WHEN saving it to the database
      address.save()
  
      # THEN the db entry is correct
      saved_address = Address.objects.last()
  
      assert saved_address.street == street
      assert saved_address.postal_code == postal_code
  
subject: Add integration test for Address model