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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 cumulative_distribution(self, X):
 """Cumulative distribution function for gaussian distribution. Arguments: X: `np.ndarray` of shape (n, 1). Returns: np.ndarray: Cumulative density for X. """

        self.check_fit()
        return norm.cdf(X, loc=self.mean, scale=self.std)