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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):
 """Perform robust single linkage clustering from features or distance matrix. Parameters X : array or sparse (CSR) matrix of shape (n_samples, n_features), or \ array of shape (n_samples, n_samples) A feature array, or array of distances between samples if ``metric='precomputed'``. Returns ------- self : object Returns self """

        X = check_array(X, accept_sparse='csr')

        kwargs = self.get_params()
        del kwargs['metric_params']
        kwargs.update(self.metric_params)

        self.labels_, self._cluster_hierarchy = robust_single_linkage(
            X, **kwargs)

        return self