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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 return_rri(self, begsam, endsam):
 """Return raw, irregularly-timed RRI."""

        interval = endsam - begsam
        dat = empty(interval)
        k = 0
            
        with open(self.filename, 'rt') as f:
            [next(f) for x in range(12)]
            
            for j, datum in enumerate(f):
                
                if begsam <= j < endsam:
                    dat[k] = float64(datum[:datum.index('\t')])
                    k += 1
                    if k == interval:
                        break
                    
        return dat