Add asyncio.taskgroups and new Task methods (#7240)

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>

tests/stubtest_allowlists/py310.txt

@@ -41,6 +41,7 @@ asyncio.Future.__init__  # Usually initialized from c object
 asyncio.Future._callbacks  # Usually initialized from c object
 asyncio.futures.Future.__init__  # Usually initialized from c object
 asyncio.futures.Future._callbacks  # Usually initialized from c object
+asyncio.taskgroups  # Added in Python 3.11
 builtins.dict.get
 contextvars.Context.__init__  # Default C __init__ signature is wrong
 contextlib.AbstractAsyncContextManager.__class_getitem__

tests/stubtest_allowlists/py36.txt

@@ -13,6 +13,7 @@ asyncio.staggered  # Added in Python 3.8
 asyncio.threads  # Added in Python 3.9
 asyncio.trsock  # Added in Python 3.8
 asyncio.mixins  # Added in Python 3.10
+asyncio.taskgroups  # Added in Python 3.11
 builtins.str.maketrans
 cmath.log
 collections.AsyncGenerator.ag_await

tests/stubtest_allowlists/py37.txt

@@ -13,6 +13,7 @@ asyncio.staggered  # Added in Python 3.8
 asyncio.threads  # Added in Python 3.9
 asyncio.trsock  # Added in Python 3.8
 asyncio.mixins  # Added in Python 3.10
+asyncio.taskgroups  # Added in Python 3.11
 builtins.dict.get
 builtins.str.maketrans
 cmath.log

tests/stubtest_allowlists/py38.txt

@@ -18,6 +18,7 @@ asyncio.futures.Future.__init__  # Usually initialized from c object
 asyncio.futures.Future._callbacks  # Usually initialized from c object
 asyncio.threads  # Added in Python 3.9
 asyncio.mixins  # Added in Python 3.10
+asyncio.taskgroups  # Added in Python 3.11
 builtins.dict.get
 collections.AsyncGenerator.ag_await
 collections.AsyncGenerator.ag_code

tests/stubtest_allowlists/py39.txt

@@ -20,6 +20,7 @@ asyncio.Future._callbacks  # Usually initialized from c object
 asyncio.futures.Future.__init__  # Usually initialized from c object
 asyncio.futures.Future._callbacks  # Usually initialized from c object
 asyncio.mixins  # Added in Python 3.10
+asyncio.taskgroups  # Added in Python 3.11
 builtins.dict.get
 collections.AsyncGenerator.ag_await
 collections.AsyncGenerator.ag_code