def line_plot(ax, x, ys, labels=None, styles=None, param_dict=None):
    """
    A helper function to make a line graph

    Parameters
    ----------
    ax : Axes
        The axes to draw to

    x : array
       The x data

    ys : array
       The y data

    labels : list
       The ys labels

    param_dict : dict
       Dictionary of kwargs to pass to ax.plot

    Returns
    -------
    out : list
        list of artists added
    """
    for i, y in enumerate(ys):
        if labels is not None:
            if styles is not None:
                ax.plot(x, y, label=labels[i], linestyle=styles[i])
            else:
                ax.plot(x, y, label=labels[i])
        else:
            ax.plot(x, y)
    if param_dict is not None:
        ax.set_xlabel(param_dict['xlabel'])  # Add an x-label to the axes.
        ax.set_ylabel(param_dict['ylabel'])  # Add a y-label to the axes.
        ax.set_title(param_dict['title'])  # Add a title to the axes.
    ax.legend()  # Add a legend
    return ax