PEP 655: Add Discussions-To link to the `typing-sig` thread (#2344)

pep-0655.rst

@@ -2,7 +2,7 @@ PEP: 655
 Title: Marking individual TypedDict items as required or potentially-missing
 Author: David Foster <david at dafoster.net>
 Sponsor: Guido van Rossum <guido at python.org>
-Discussions-To: typing-sig at python.org
+Discussions-To: https://mail.python.org/archives/list/typing-sig@python.org/thread/53XVOD5ZUKJ263MWA6AUPEA6J7LBBLNV/
 Status: Draft
 Type: Standards Track
 Content-Type: text/x-rst
@@ -315,7 +315,7 @@ Usage in Python <3.11
 If your code supports Python <3.11 and wishes to use ``Required[]`` or
 ``NotRequired[]`` then it should use ``typing_extensions.TypedDict`` rather
 than ``typing.TypedDict`` because the latter will not understand
-``(Not)Required[]``. In particular ``__required_keys__`` and 
+``(Not)Required[]``. In particular ``__required_keys__`` and
 ``__optional_keys__`` on the resulting TypedDict type will not be correct:
 
 Yes (Python 3.11+ only):
@@ -346,11 +346,11 @@ No (Python <3.11 and 3.11+):
 
    from typing import TypedDict  # oops: should import from typing_extensions instead
    from typing_extensions import NotRequired
-   
+
    class Movie(TypedDict):
        title: str
        year: NotRequired[int]
-   
+
    assert Movie.__required_keys__ == frozenset({'title', 'year'})  # yikes
    assert Movie.__optional_keys__ == frozenset()  # yikes
 
@@ -464,7 +464,7 @@ as the type of a variable which is only conditionally defined:
 
    class MyClass:
        attr: int|Missing
-       
+
        def __init__(self, set_attr: bool) -> None:
            if set_attr:
                self.attr = 10
@@ -533,7 +533,7 @@ or a check against ``locals()`` for local variables:
        packet_bytes: Union[str, Missing]
        if packet_data is not None:
            packet_bytes = packet.data.encode('utf-8')
-       
+
        if 'packet_bytes' in locals():
            reveal_type(packet_bytes)  # bytes
            socket.send(packet_bytes)