bpo-39481: Implementation for PEP 585 (#18239)
This implements things like `list[int]`,
which returns an object of type `types.GenericAlias`.
This object mostly acts as a proxy for `list`,
but has attributes `__origin__` and `__args__`
that allow recovering the parts (with values `list` and `(int,)`.
There is also an approximate notion of type variables;
e.g. `list[T]` has a `__parameters__` attribute equal to `(T,)`.
Type variables are objects of type `typing.TypeVar`.
diff --git a/Lib/test/test_doctest.py b/Lib/test/test_doctest.py
index 9e88222..7142627 100644
--- a/Lib/test/test_doctest.py
+++ b/Lib/test/test_doctest.py
@@ -665,7 +665,7 @@
>>> import builtins
>>> tests = doctest.DocTestFinder().find(builtins)
- >>> 800 < len(tests) < 820 # approximate number of objects with docstrings
+ >>> 810 < len(tests) < 830 # approximate number of objects with docstrings
True
>>> real_tests = [t for t in tests if len(t.examples) > 0]
>>> len(real_tests) # objects that actually have doctests