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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 get_resolve_url(self, did_bytes):
 """Return a did value and value type from the block chain event record using 'did'. :param did_bytes: DID, hex-str :return url: Url, str """

        data = self._did_registry.get_registered_attribute(did_bytes)
        if not (data and data.get('value')):
            return None

        return data['value']