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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 _transform_col(self, x, col):
 """Normalize one numerical column. Args: x (numpy.array):
 a numerical column to normalize col (int):
 column index Returns: A normalized feature vector. """


        return norm.ppf(self.ecdfs[col](x) * .998 + .001)