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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 reference(self):
 """Make relations point to ontology terms instead of term ids. This is done automatically when using the :obj:`merge` and :obj:`include` methods as well as the :obj:`__init__` method, but it should be called in case of manual changes of the relationships of a Term. """

        for termkey, termval in six.iteritems(self.terms):
            termval.relations.update(
                (relkey, TermList(
                    (self.terms.get(x) or Term(x, '', '')
                    if not isinstance(x, Term) else x) for x in relval
                )) for relkey, relval in six.iteritems(termval.relations)
            )