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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 calc_mean_and_variance_of_variances(self, NumberOfOscillations):
 """ Calculates the mean and variance of a set of varainces. This set is obtained by splitting the timetrace into chunks of points with a length of NumberOfOscillations oscillations. Parameters NumberOfOscillations : int The number of oscillations each chunk of the timetrace used to calculate the variance should contain. Returns ------- Mean : float Variance : float """

        SplittedArraySize = int(self.SampleFreq/self.FTrap.n) * NumberOfOscillations
        VoltageArraySize = len(self.voltage)
        SnippetsVariances = _np.var(self.voltage[:VoltageArraySize-_np.mod(VoltageArraySize,SplittedArraySize)].reshape(-1,SplittedArraySize),axis=1)

        return _np.mean(SnippetsVariances), _np.var(SnippetsVariances)