def get_dir_from_zipfile(zip_file, fallback=None):
    """Return the name of the root folder in a zip file.

    :param zip_file: a :class:`zipfile.ZipFile` instance.
    :param fallback: if `None`, the name of the zip file is used. This is
        returned if the zip file contains more than one top-level directory,
        or none at all.
    """
    fallback = fallback or zip_file.filename
    directories = [name for name in zip_file.namelist() if name.endswith("/")
                   and len(PurePath(name).parts) == 1]
    return fallback if len(directories) > 1 else directories[0]
def test_to_dict_returns_correct_dict(self):
        self.voiceover_application.accept(self.reviewer_id)
        expected_dict = {
            'voiceover_application_id': 'application_id',
            'target_type': 'exploration',
            'target_id': 'exp_id',
            'status': 'accepted',
            'author_name': 'author',
            'final_reviewer_name': 'reviewer',
            'language_code': 'en',
            'content': '<p>Content</p>',
            'filename': 'audio_file.mp3',
            'rejection_message': None
        }
        self.assertEqual(
            self.voiceover_application.to_dict(), expected_dict)