Pending removal in Python 3.17#

• "collections.abc":

• "collections.abc.ByteString" is scheduled for removal in Python 3.17.

  Use "isinstance(obj, collections.abc.Buffer)" to test if "obj" implements the buffer protocol at runtime. For use in type annotations, either use "Buffer" or a union that explicitly specifies the types your code supports (e.g., "bytes | bytearray | memoryview").

  "ByteString" was originally intended to be an abstract class that would serve as a supertype of both "bytes" and "bytearray". However, since the ABC never had any methods, knowing that an object was an instance of "ByteString" never actually told you anything useful about the object. Other common buffer types such as "memoryview" were also never understood as subtypes of "ByteString" (either at runtime or by static type checkers).

  See PEP 688 for more details. (Contributed by Shantanu Jain in gh-91896.)

• "typing":

• Before Python 3.14, old-style unions were implemented using the private class "typing._UnionGenericAlias". This class is no longer needed for the implementation, but it has been retained for backward compatibility, with removal scheduled for Python 3.17. Users should use documented introspection helpers like "typing.get_origin()" and "typing.get_args()" instead of relying on private implementation details.

• "typing.ByteString", deprecated since Python 3.9, is scheduled for removal in Python 3.17.

  Use "isinstance(obj, collections.abc.Buffer)" to test if "obj" implements the buffer protocol at runtime. For use in type annotations, either use "Buffer" or a union that explicitly specifies the types your code supports (e.g., "bytes | bytearray | memoryview").

  "ByteString" was originally intended to be an abstract class that would serve as a supertype of both "bytes" and "bytearray". However, since the ABC never had any methods, knowing that an object was an instance of "ByteString" never actually told you anything useful about the object. Other common buffer types such as "memoryview" were also never understood as subtypes of "ByteString" (either at runtime or by static type checkers).

  See PEP 688 for more details. (Contributed by Shantanu Jain in gh-91896.)