def _create_pred_input_plot(mean, error, axes, **kwargs):
    """Create plot for prediction input data (vertical lines)."""
    vspan_kwargs = dict(kwargs)
    vspan_kwargs['alpha'] = max([kwargs.get('alpha', 1.0) - 0.2, 0.1])
    vspan_kwargs.pop('label', None)
    axes.axvline(mean, **kwargs)
    axes.axvspan(mean - error, mean + error, **vspan_kwargs)
    return axes