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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, **kwargs):
 """ Fits the estimator to discover the feature importances described by the data, then draws those importances as a bar plot. Parameters X : ndarray or DataFrame of shape n x m A matrix of n instances with m features y : ndarray or Series of length n An array or series of target or class values kwargs : dict Keyword arguments passed to the fit method of the estimator. Returns ------- self : visualizer The fit method must always return self to support pipelines. """

        super(FeatureImportances, self).fit(X, y, **kwargs)

        # Get the feature importances from the model
        self.feature_importances_ = self._find_importances_param()

        # Get the classes from the model
        if is_classifier(self):
            self.classes_ = self._find_classes_param()
        else:
            self.classes_ = None
            self.stack = False

        # If self.stack = True and feature importances is a multidim array,
        # we're expecting a shape of (n_classes, n_features)
        # therefore we flatten by taking the average by
        # column to get shape (n_features,)  (see LogisticRegression)
        if not self.stack and self.feature_importances_.ndim > 1:
            self.feature_importances_ = np.mean(self.feature_importances_, axis=0)
            warnings.warn((
                "detected multi-dimensional feature importances but stack=False, "
                "using mean to aggregate them."
            ), YellowbrickWarning)

        # Apply absolute value filter before normalization
        if self.absolute:
            self.feature_importances_ = np.abs(self.feature_importances_)

        # Normalize features relative to the maximum
        if self.relative:
            maxv = np.abs(self.feature_importances_).max()
            self.feature_importances_ /= maxv
            self.feature_importances_ *= 100.0

        # Create labels for the feature importances
        # NOTE: this code is duplicated from MultiFeatureVisualizer
        if self.labels is None:
            # Use column names if a dataframe
            if is_dataframe(X):
                self.features_ = np.array(X.columns)

            # Otherwise use the column index as the labels
            else:
                _, ncols = X.shape
                self.features_ = np.arange(0, ncols)
        else:
            self.features_ = np.array(self.labels)

        # Sort the features and their importances
        if self.stack:
            sort_idx = np.argsort(np.mean(self.feature_importances_, 0))
            self.features_ = self.features_[sort_idx]
            self.feature_importances_ = self.feature_importances_[:, sort_idx]
        else:
            sort_idx = np.argsort(self.feature_importances_)
            self.features_ = self.features_[sort_idx]
            self.feature_importances_ = self.feature_importances_[sort_idx]

        # Draw the feature importances
        self.draw()
        return self