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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 serialize(self, datas):
 """ Serialize datas to manifest structure with metas and references. Only references are returned, metas are assigned to attribute ``ManifestSerializer._metas``. Arguments: datas (dict):
 Data where to search for reference declarations. This is commonly the fully parsed manifest. Returns: collections.OrderedDict: Serialized enabled references datas. """

        self._metas = OrderedDict({
            'references': self.get_meta_references(datas),
        })

        return self.get_enabled_references(datas, self._metas['references'])