TypeDict "dict style" positional arguments

Hi.
I'm just curious why passing arguments to TypeDict is strictly constrained. I tried some variants including positional arguments style and failed. It's not reflected in docs or function signature (ctrl + p in Pycharm)
https://docs.python.org/3/library/typing.html#typing.TypedDict

In [1]: from typing import TypedDict                                                                                                                                                                       

In [2]:  
   ...: ProfileText = TypedDict(name='ProfileText', fields={'name': str, 'non variable key': str}, total=False)  # Error                                                                                   
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-2-7d3b7c9254f3> in <module>
----> 1 ProfileText = TypedDict(name='ProfileText', fields={'name': str, 'non variable key': str}, total=False)  # Error

TypeError: _typeddict_new() missing 1 required positional argument: 'typename'

In [3]:  
   ...: ProfileText = TypedDict('ProfileText', {'name': str, 'non variable key': str}, total=False)  # Error                                                                                               

In [4]:  
   ...: ProfileText = TypedDict('ProfileText', {'name': str, 'non variable key': str}, False)  # Error                                                                                                     
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-4-b3b55e028c98> in <module>
----> 1 ProfileText = TypedDict('ProfileText', {'name': str, 'non variable key': str}, False)  # Error

TypeError: _typeddict_new() takes from 2 to 3 positional arguments but 4 were given

In [5]:  

The issue mentions the TypedDict entry point and the Python typing documentation; start by comparing the shown keyword and positional call forms with that documentation. Determine which calling convention should be supported, then define completion as aligned behavior, signature information, documentation, and tests for the accepted form.