def mpl_hist_arg(value=True):
    """Find the appropriate `density` kwarg for our given matplotlib version.

    This will determine if we should use `normed` or `density`. Additionally,
    since this is a kwarg, the user can supply a value (True or False) that
    they would like in the output dictionary.

    Parameters
    ----------
    value : bool, optional (default=True)
        The boolean value of density/normed

    Returns
    -------
    density_kwarg : dict
        A dictionary containing the appropriate density kwarg for the
        installed  matplotlib version, mapped to the provided or default
        value
    """
    import matplotlib
    density_kwarg = ('density' if matplotlib.__version__ >= '2.1.0' else
        'normed')
    return {density_kwarg: value}
