def test_storage_methods(self):
        storage = QueuedStorage(
            'django.core.files.storage.FileSystemStorage',
            'django.core.files.storage.FileSystemStorage')

        file_storage = Storage()

        for attr in dir(file_storage):
            method = getattr(file_storage, attr)

            if not callable(method):
                continue

            method = getattr(storage, attr, False)
            self.assertTrue(callable(method),
                            "QueuedStorage has no method '%s'" % attr)
Make sure that QueuedStorage implements all the methods
dataset/ETHPy150Open jazzband/django-queued-storage/tests/test_storages.py/StorageTests.test_storage_methods