anchor.diff:  ```
   === `asyncio.run()` is now a stable API
   
  +~~~
  +
  +TODO: for 3.5 and lower 
   
   
  
positive.code: :link:https://docs.python.org/3.9/whatsnew/3.9.html
  
  === Dictionary merge and update `a|b` or `a|=b`
  === Type hinting generics in standard collections: `list[str]`, `dict[str, int]` 
  
  == 3.8 
  
negative.code: :link:https://docs.python.org/3.8/whatsnew/3.8.html 
  
  === Assignment expression aka walrus operator `:=`
  ```python
  # re search
  discount = 0.0
  if (mo := re.search(r'(\d+)% discount', advertisement)):
  