def new_filename_from_old(old_filename, new_filenames):
    """
    From a list of new file names, find the new name
    that corresponds with the old file name based on the file extension
    """
    new_filename = None
    try:
        extension = old_filename.split(".")[-1]
    except AttributeError:
        extension = None
    if extension:
        for filename in new_filenames:
            new_extension = filename.split(".")[-1]
            if new_extension and extension == new_extension:
                new_filename = filename
    return new_filename