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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 draw_widget(self, item):
 """Create a preview of the selected treeview item"""

        if item:
            self.filter_remove(remember=True)
            selected_id = self.treedata[item]['id']
            item = self.get_toplevel_parent(item)
            widget_id = self.treedata[item]['id']
            wclass = self.treedata[item]['class']
            xmlnode = self.tree_node_to_xml('', item)
            self.previewer.draw(item, widget_id, xmlnode, wclass)
            self.previewer.show_selected(item, selected_id)
            self.filter_restore()