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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 getSampleFrequency(self,chn):
 """ Returns the samplefrequency of signal edfsignal. Parameters chn : int channel number Examples -------- True """

        if 0 <= chn < self.signals_in_file:
            return round(self.samplefrequency(chn))
        else:
            return 0