def METHOD_NAME(potential, f):
    """
    Write a :class:`~gala.potential.PotentialBase` object out to a text (YAML)
    file.
    Parameters
    ----------
    potential : :class:`~gala.potential.PotentialBase`
        The instantiated :class:`~gala.potential.PotentialBase` object.
    f : str, file_like
        A filename or file-like object to write the input potential object to.
    """
    d = to_dict(potential)
    if hasattr(f, "write"):
        yaml.dump(d, f, default_flow_style=None)
    else:
        with open(f, "w") as f2:
            yaml.dump(d, f2, default_flow_style=None)