def filter_thumbnail_files(chan_path, filenames, metadata_provider):
    """
    We don't want to create `ContentNode` from thumbnail files.
    """
    thumbnail_files_to_skip = metadata_provider.get_thumbnail_paths()
    filenames_cleaned = []
    for filename in filenames:
        keep = True
        chan_filepath = os.path.join(chan_path, filename)
        chan_filepath_tuple = path_to_tuple(chan_filepath)
        if chan_filepath_tuple in thumbnail_files_to_skip:
            keep = False
        if keep:
            filenames_cleaned.append(filename)
    return filenames_cleaned
We don't want to create `ContentNode` from thumbnail files.