code: def forwards(self, orm):
          "Write your forwards methods here."
          # Note: Don't use "from appname.models import ModelName". 
          # Use orm.ModelName to refer to models in this application,
          # and orm['appname.ModelName'] for models in other applications.
          from account_keeping.models import Invoice
          for invoice in Invoice.objects.all():
              invoice.save(f forwards(self, orm):
          "Write your forwards methods here."
          # Note: Don't use "from appname.models import ModelName". 
          # Use orm.ModelName to refer to models in this application,
          # and orm['appname.ModelName'] for models in other applications.
          from account_keeping.models import Invoice
          for invoice in Invoice.objects.all():
              invoice.save()
docs: Write your forwards methods here.