Create a backup with a tqdm progress bar.

def _backup_pb_tqdm(self, dirs):
        """Create a backup with a tqdm progress bar."""
        with ZipFile(self.zip_filename, 'w') as backup_zip:
            for path in tqdm(dirs, desc='Writing Zip Files', total=len(dirs)):
                backup_zip.write(path, path[len(self.source):len(path)])