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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 add_public_key(self, did, public_key):
 """ Add a public key object to the list of public keys. :param public_key: Public key, PublicKeyHex """

        logger.debug(f'Adding public key {public_key} to the did {did}')
        self._public_keys.append(
            PublicKeyBase(did, **{"owner": public_key, "type": "EthereumECDSAKey"}))