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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 plot_ticks(ax, tick_fontsize=12, xticks=None, xticks_args=None, yticks=None, yticks_args=None, zticks=None, zticks_args=None):
 """Function that defines the labels options of a matplotlib plot. Args: ax: matplotlib axes tick_fontsize (int):
 Defines the size of the ticks' font xticks([list of ticks]):
 Defines the values of x ticks in the figure xticks_arg(dict):
 Passsed into matplotlib as xticks arguments yticks([list of ticks]):
 Defines the values of y ticks in the figure yticks_arg(dict):
 Passsed into matplotlib as yticks arguments zticks([list of ticks]):
 Defines the values of z ticks in the figure zticks_arg(dict):
 Passsed into matplotlib as zticks arguments """

    if xticks is not None:
        ax.set_xticks(xticks)
        xticks_args = dict_if_none(xticks_args)
        ax.xaxis.set_tick_params(labelsize=tick_fontsize, **xticks_args)

    if yticks is not None:
        ax.set_yticks(yticks)
        yticks_args = dict_if_none(yticks_args)
        ax.yaxis.set_tick_params(labelsize=tick_fontsize, **yticks_args)

    if zticks is not None:
        ax.set_zticks(zticks)
        zticks_args = dict_if_none(zticks_args)
        ax.zaxis.set_tick_params(labelsize=tick_fontsize, **zticks_args)