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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 get_stride(self):
 """Calculate the stride for the spectrogram This method returns the stride as a `float`, or `None` to indicate selected usage of `TimeSeries.spectrogram2`. """

        fftlength = float(self.args.secpfft)
        overlap = fftlength * self.args.overlap
        stride = fftlength - overlap
        nfft = self.duration / stride  # number of FFTs
        ffps = int(nfft / (self.width * 0.8))  # FFTs per second
        if ffps > 3:
            return max(2 * fftlength, ffps * stride + fftlength - 1)
        return None