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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 describe(self):
 """ Returns a list of strings, one for each feature selected, with human-readable descriptions of the features. Returns ------- labels : list of str An ordered list of strings, one for each feature selected, with human-readable descriptions of the features. """

        all_labels = []
        for f in self.active_features:
            all_labels += f.describe()
        return all_labels