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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):
 """ Construct a dictionary of string -> labels Returns: -------- OrderedDict<str, int> : string label pairs. """

        labelings = OrderedDict()
        for tree in self:
            for label, line in tree.to_labeled_lines():
                labelings[line] = label
        return labelings