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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 background_time(self):
 """Return the amount of background time that the buffers contain"""

        time = 1.0 / self.timeslide_interval
        for ifo in self.singles:
            time *= self.singles[ifo].filled_time * self.analysis_block
        return time