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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 remove(self):
 """ Removes an item from ListNode. Raises: TypeError: If it's called on container ListNode (intstead of ListNode's item) Note: Parent object should be explicitly saved. """

        if not self._is_item:
            raise TypeError("Should be called on an item, not ListNode's itself.")
        self.container.node_stack.remove(self)