On 2002 Sept 14, the following was merged into editor.py (then EditorWindow.py) as part of the smart indenting code added to the bottom.

import tokenize
_tokenize
del tokenize

This now would usually be written "import tokenize as _tokenize".  Stdlib modules without explicit __all__ often do this to omit stdlib modules from their public interface.  Idlelib does not do this.  Add to README import standards.  I put replaced the above with 'import tokenize' as the top where is belongs and changed all '_tokenize' to 'tokenize'.