def fill_subparser(subparser):
    """Sets up a subparser to convert the MNIST dataset files.

    Parameters
    ----------
    subparser : :class:`argparse.ArgumentParser`
        Subparser handling the `mnist` command.

    """
    subparser.add_argument(
        "--dtype", help="dtype to save to; by default, images will be " +
        "returned in their original unsigned byte format",
        choices=('float32', 'float64', 'bool'), type=str, default=None)
    return convert_mnist
Sets up a subparser to convert the MNIST dataset files.

    Parameters
    ----------
    subparser : :class:`argparse.ArgumentParser`
        Subparser handling the `mnist` command.