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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 fit(self, X, y=None, **fit_params):
 """Fit the StackingEstimator meta-transformer. Parameters X: array-like of shape (n_samples, n_features) The training input samples. y: array-like, shape (n_samples,) The target values (integers that correspond to classes in classification, real numbers in regression). fit_params: Other estimator-specific parameters. Returns ------- self: object Returns a copy of the estimator """

        self.estimator.fit(X, y, **fit_params)
        return self