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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 stretch_weber_fechner(self, k, s0):
 """Stretch according to the Weber-Fechner law. p = k.ln(S/S0) p is perception, S is the stimulus, S0 is the stimulus threshold (the highest unpercieved stimulus), and k is the factor. """

        attrs = self.data.attrs
        self.data = k * xu.log(self.data / s0)
        self.data.attrs = attrs