[issue39317] This new feature or bug about operator "- -"?

[dai dai]

New submission from dai dai <daidai4269 at gmail.com>:

```py
print(3 - - 2)
print(3 + + 2)
"""output
5
5
"""
```

----------
components: Windows
messages: 359886
nosy: dai dai, paul.moore, steve.dower, tim.golden, zach.ware
priority: normal
severity: normal
status: open
title: This new feature or bug about operator "- -"?
type: behavior
versions: Python 3.7

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue39317>
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