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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 labels(self):
 """Retrieve or set labels assigned to this bucket. See https://cloud.google.com/storage/docs/json_api/v1/buckets#labels .. note:: The getter for this property returns a dict which is a *copy* of the bucket's labels. Mutating that dict has no effect unless you then re-assign the dict via the setter. E.g.: :setter: Set labels for this bucket. :getter: Gets the labels for this bucket. :rtype: :class:`dict` :returns: Name-value pairs (string->string) labelling the bucket. """

        labels = self._properties.get("labels")
        if labels is None:
            return {}
        return copy.deepcopy(labels)