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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 addSpectrogram(self, ydata, fs, title=None):
 """Adds a new spectorgram plot for the given image. Generates a SpecWidget :param ydata: 2-D array of the image to display :type ydata: numpy.ndarray :param fs: the samplerate of the signal in the image, used to set time/ frequency scale :type fs: int :param title: Plot title :type title: str """

        p = SpecWidget()
        p.updateData(ydata, fs)
        if title is not None:
            p.setTitle(title)
        self.stacker.addWidget(p)