from typing import TypeAliasType as typing_TA
from typing_extensions import TypeAliasType

# this should raise an error
Simple = TypeAliasType("Simple", int)
Simple_typing = typing_TA("Simple", int)
try:
   Simple[str]  # No TypeError
except TypeError:
   print("TypeError raised like expected")
else:
   print("No type error was raised.")  # <-- will be printed

Simple_typing[str] # will raise TypeError

from typing import TypeAliasType as typing_TA
Simple2 = typing_TA("Simple", int, type_params=())
Simple2[str]  # no type error for typing.TypeAliasType