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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 _set_mixed_moments_to_zero(self, closed_central_moments, n_counter):
 r""" In univariate case, set the cross-terms to 0. :param closed_central_moments: matrix of closed central moment :param n_counter: a list of :class:`~means.core.descriptors.Moment`\s representing central moments :type n_counter: list[:class:`~means.core.descriptors.Moment`] :return: a matrix of new closed central moments with cross-terms equal to 0 """


        positive_n_counter = [n for n in n_counter if n.order > 1]
        if self.is_multivariate:
            return closed_central_moments
        else:
            return [0 if n.is_mixed else ccm for n,ccm in zip(positive_n_counter, closed_central_moments)]