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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 _init(self, *args, **kwargs):
 """ _deps is used for common dependencies. When a expr depend on other exprs, and the expr is not calculated from the others, the _deps are specified to identify the dependencies. """

        self._init_attr('_deps', None)

        self._init_attr('_ban_optimize', False)
        self._init_attr('_engine', None)
        self._init_attr('_Expr__execution', None)

        self._init_attr('_need_cache', False)
        self._init_attr('_mem_cache', False)

        if '_id' not in kwargs:
            kwargs['_id'] = new_id()

        super(Expr, self)._init(*args, **kwargs)