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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 timeseries(self, dataframe=False):
 """Get BMIPR as a time series."""


        closed_timeseries = self.closed.timeseries(dataframe=dataframe)
        opened_timeseries = self.opened.timeseries(dataframe=dataframe)
        return calculate_bmi(closed_timeseries, opened_timeseries)