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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 validate_reference_data(self, ref_data):
 """Validate the reference data. Zotero.check_items() caches data after the first API call. """

        try:
            self._zotero_lib.check_items([ref_data])
        except InvalidItemFields as e:
            raise InvalidZoteroItemError from e