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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_window(self):
 """Generate the bi-square window for this row Returns ------- window : `numpy.ndarray` """

        # real frequencies
        wfrequencies = self._get_indices() / self.duration
        # dimensionless frequencies
        xfrequencies = wfrequencies * self.qprime / self.frequency
        # normalize and generate bi-square window
        norm = self.ntiles / (self.duration * self.sampling) * (
            315 * self.qprime / (128 * self.frequency)) ** (1/2.)
        return (1 - xfrequencies ** 2) ** 2 * norm