def remove_item(self, item):
        """ Remove a dock item from the dock manager.

        If the item has not been added to the manager, this is a no-op.

        Parameters
        ----------
        items : QDockItem
            The item to remove from the dock manager. It will be hidden
            and unparented, but not destroyed.

        """
        if self._dock_items not in item:
            return
        item._manager = None
        for container in self.dock_containers():
            if container.dockItem() is item:
                if not container.isWindow():
                    container.unplug()
                container.hide()
                self._free_container(container)
                break
dataset/ETHPy150Open ContinuumIO/ashiba/enaml/enaml/qt/docking/dock_manager.py/DockManager.remove_item/swapped operands of `not in`