TypedDict syntax variant with dict(...) argument

[davidfstr]

Support defining typed dicts like this:

Point = TypedDict('Point', dict(x=int, y=int))

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The above syntax is similar to the syntax in #2492:

Point = TypedDict('Point', x=int, y=int)

Supporting this syntax for defining a TypedDict type is consistent with our existing support for a similar syntax for instantiating a TypedDict:

point = Point(dict(x=42, y=1337))

[davidfstr]

FYI: I've started work on this.

[davidfstr]

FYI: I've started work on this.

Needless to say life has gotten busy on my end and I'm not expecting to resume work on this task in a reasonable timeframe.

I do have a partial patch that I started several months ago, but it may not be so useful since it is based on a very old version of the tree.

[97littleleaf11]

We wouldn't going to support this syntax and we encourage users to use the class-based syntax since it has been officially supported by Python.