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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_ax_labels(ax=None, xlabel=None, ylabel=None, xticks=None, yticks=None, label_fontsize=18):
 """Set all axis labels properties easily. Parameters ax : matplotlib AxesSubplot object (optional) Axis to set. If None, uses current axis. Default is None. xlabel : None or string (optional) x axis label. Default is None. ylabel : None or string (optional) y axis label. Default is None. xticks : None or False or list of numbers xticks. If False, ticks are hidden. Default is None. yticks : None or False or list of numbers yticks. If False, ticks are hidden. Default is None. label_fontsize : number Fontsize of label. Default is 18. See Also -------- set_fig_labels """

    # get ax
    if ax is None:
        ax = plt.gca()
    # x
    if xlabel is not None:
        ax.set_xlabel(xlabel, fontsize=label_fontsize)
    if xticks is not None:
        if isinstance(xticks, bool):
            plt.setp(ax.get_xticklabels(), visible=xticks)
            if not xticks:
                ax.tick_params(axis="x", which="both", length=0)
        else:
            ax.set_xticks(xticks)
    # y
    if ylabel is not None:
        ax.set_ylabel(ylabel, fontsize=label_fontsize)
    if yticks is not None:
        if isinstance(yticks, bool):
            plt.setp(ax.get_yticklabels(), visible=yticks)
            if not yticks:
                ax.tick_params(axis="y", which="both", length=0)
        else:
            ax.set_yticks(yticks)