TypedDict alternative definition syntax with keyword args is confusing

[97littleleaf11]

Originally opened in https://bugs.python.org/issue46066.
Related discussion: python/mypy#2492

According to the documentation, there are two additional equivalent syntax for TypedDict definition:

Point2D = TypedDict('Point2D', x=int, y=int, label=str)
Point2D = TypedDict('Point2D', {'x': int, 'y': int, 'label': str})

However, the former one is quite confusing since we have the total keyword arg for TypedDict. In addition, PEP589 doesn't have this syntax.

I think we could just deprecated it and remove it from the doc.