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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 file_renamed(self, editor, new_filename):

 """File was renamed, updating outline explorer tree"""

        if editor is None:
            # This is needed when we can't find an editor to attach
            # the outline explorer to.
            # Fix issue 8813
            return
        editor_id = editor.get_id()
        if editor_id in list(self.editor_ids.values()):
            root_item = self.editor_items[editor_id]
            root_item.set_path(new_filename, fullpath=self.show_fullpath)
            self.__sort_toplevel_items()