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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 read_multi_vars(self, items):
 """This function read multiple variables from the PLC. :param items: list of S7DataItem objects :returns: a tuple with the return code and a list of data items """

        result = self.library.Cli_ReadMultiVars(self.pointer, byref(items),
                                                c_int32(len(items)))
        check_error(result, context="client")
        return result, items