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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 iterator_zip(variables: VarType, parent: str = None) -> Iterable[VarMatrix]: """Apply the zip operator to a set of variables. This uses the python zip iterator to combine multiple lists of variables such that the nth variable in each list is aligned. Args: variables: The variables object parent: Unused """


    logger.debug("Yielding from zip iterator")
    if isinstance(variables, list):
        for item in variables:
            yield list(variable_matrix(item, parent, "zip"))
    else:
        yield list(variable_matrix(variables, parent, "zip"))