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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 setup_xrange(self, xrange):
        '''setup plotting ticks on x axis'''
        if self.xaxis:
            return
        xrange *= 24 * 60 * 60
        interval = 1
        intervals = [ 1, 2, 5, 10, 15, 30, 60, 120, 240, 300, 600,
                      900, 1800, 3600, 7200, 5*3600, 10*3600, 24*3600 ]
        for interval in intervals:
            if xrange / interval < 12:
                break
        self.locator = matplotlib.dates.SecondLocator(interval=interval)
        self.ax1.xaxis.set_major_locator(self.locator)