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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_fig_title(self, title, **kwargs):
 """Set overall figure title. Set title for overall figure. This is not for a specific plot. It will place the title at the top of the figure with a call to ``fig.suptitle``. Args: title (str):
 Figure title. Keywork Arguments: x/y (float, optional):
 The x/y location of the text in figure coordinates. Defaults are 0.5 for x and 0.98 for y. horizontalalignment/ha (str, optional):
 The horizontal alignment of the text relative to (x, y). Optionas are 'center', 'left', or 'right'. Default is 'center'. verticalalignment/va (str, optional):
 The vertical alignment of the text relative to (x, y). Optionas are 'top', 'center', 'bottom', or 'baseline'. Default is 'top'. fontsize/size (int, optional):
 The font size of the text. Default is 20. """

        prop_default = {
            'fontsize': 20,
        }

        for prop, default in prop_default.items():
            kwargs[prop] = kwargs.get(prop, default)

        self.figure.fig_title = title
        self.figure.fig_title_kwargs = kwargs
        return