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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_x_label(self, xlabel, **kwargs):
 """Set overall figure x. Set label for x axis on overall figure. This is not for a specific plot. It will place the label on the figure at the left with a call to ``fig.text``. Args: xlabel (str):
 xlabel for entire figure. Keyword Arguments: x/y (float, optional):
 The x/y location of the text in figure coordinates. Defaults are 0.01 for x and 0.51 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 'center'. fontsize/size (int):
 The font size of the text. Default is 20. rotation (float or str):
 Rotation of label. Options are angle in degrees, `horizontal`, or `vertical`. Default is `vertical`. Note: Other kwargs are available. See https://matplotlib.org/api/pyplot_api.html#matplotlib.pyplot.figtext """

        prop_default = {
            'x': 0.01,
            'y': 0.51,
            'fontsize': 20,
            'rotation': 'vertical',
            'va': 'center',
        }

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

        self._set_fig_label('x', xlabel, **kwargs)
        return