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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 squelch(self, threshold):
 """ Set all records that do not exceed the given threhsold to 0. Parameters threshold : scalar Level below which to set records to zero """

        func = lambda x: zeros(x.shape) if max(x) < threshold else x
        return self.map(func)