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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 standardize(self, axis=1):
 """ Divide by standard deviation either within or across records. Parameters axis : int, optional, default = 0 Which axis to standardize along, within (1) or across (0) records """

        if axis == 1:
            return self.map(lambda x: x / std(x))
        elif axis == 0:
            stdval = self.std().toarray()
            return self.map(lambda x: x / stdval)
        else:
            raise Exception('Axis must be 0 or 1')