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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_define(transform):
 """ This function links the user's choice of transformation with the associated numpy function """

        if transform == 'tanh':
            return np.tanh
        elif transform == 'exp':
            return np.exp
        elif transform == 'logit':
            return Family.ilogit
        elif transform is None:
            return np.array
        else:
            return None