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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 new(self, attribute, operation=ChainOperator.AND):
 """ Combine with a new query :param str attribute: attribute of new query :param ChainOperator operation: operation to combine to new query :rtype: Query """

        if isinstance(operation, str):
            operation = ChainOperator(operation)
        self._chain = operation
        self._attribute = self._get_mapping(attribute) if attribute else None
        self._negation = False
        return self