docs: 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'])