'Remove the :class:`.NodeItem` instance that was previously
constructed for a :class:`SchemeNode` `node` using the `add_node`
method.'

def remove_node(self, node):

    item = self.__item_for_node.pop(node)
    node.position_changed.disconnect(self.__on_node_pos_changed)
    node.title_changed.disconnect(item.setTitle)
    node.progress_changed.disconnect(item.setProgress)
    node.processing_state_changed.disconnect(item.setProcessingState)
    node.state_message_changed.disconnect(item.setStateMessage)
    self.remove_node_item(item)
