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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_current_block_hash(self, is_full: bool = False) -> str: """ This interface is used to get the hexadecimal hash value of the highest block in current network. Return: the hexadecimal hash value of the highest block in current network. """

        payload = self.generate_json_rpc_payload(RpcMethod.GET_CURRENT_BLOCK_HASH)
        response = self.__post(self.__url, payload)
        if is_full:
            return response
        return response['result']