Work around issue 10827

from django.test import TransactionTestCase as DjangoTransactionTestCase

[...]


class TransactionTestCase(DjangoTransactionTestCase):
    """
    Works around Django issue 10827 by clearing the ContentType cache
    before permissions are setup.
    """
    def _pre_setup(self, *args, **kwargs):
        ContentType.objects.clear_cache()
        super(TransactionTestCase, self)._pre_setup(*args, **kwargs)