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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_default_format(self, vmin, vmax):
        "Returns the default ticks spacing."

        if self.plot_obj.date_axis_info is None:
            self.plot_obj.date_axis_info = self.finder(vmin, vmax, self.freq)
        info = self.plot_obj.date_axis_info

        if self.isminor:
            format = np.compress(info['min'] & np.logical_not(info['maj']),
                                 info)
        else:
            format = np.compress(info['maj'], info)
        self.formatdict = {x: f for (x, _, _, f) in format}
        return self.formatdict