def blank(*args):
    """
    Create the string representation of a blank hierarchy.

    Generally, this will be used as an input to the kind argument in
    <phoebe.frontend.bundle.Bundle.set_hierarchy>.  If attaching through
    <phoebe.frontend.bundle.Bundle.set_hierarchy>, all `**kwargs` will be
    passed on to set the values as described in the arguments below.

    Arguments
    ----------
    * `*args`: IGNORED

    Returns
    --------
    * (str): the string representation of the hierarchy, ready to be sent to
        <phoebe.frontend.bundle.Bundle.set_hierarchy>.
    """
    return ''
