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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"typing._type_check no longer recognizes several kinds of non-types","articleBody":"**Bug report**\r\n\r\nThe internal function `typing._type_check()` is used extensively to check whether a particular value represents a type. Its docstring begins with:\r\n\r\n```\r\ndef _type_check(arg, msg, is_argument=True, module=None, *, allow_special_forms=False):\r\n    \"\"\"Check that the argument is a type, and return it (internal helper).\r\n```\r\n\r\nIn Python 3.11b1 this function no longer errors on various kinds of non-types:\r\n\r\n```python\r\n\u003e\u003e\u003e import sys\r\n\u003e\u003e\u003e sys.version_info\r\nsys.version_info(major=3, minor=11, micro=0, releaselevel='beta', serial=1)\r\n\u003e\u003e\u003e import typing\r\n\u003e\u003e\u003e typing._type_check(5, \"Expected a type.\")\r\n# no error!\r\n\u003e\u003e\u003e typing.ClassVar[5]\r\ntyping.ClassVar[5]  # no error!\r\n```\r\n\r\nBy contrast on Python 3.10:\r\n\r\n```python\r\n\u003e\u003e\u003e import sys\r\n\u003e\u003e\u003e sys.version_info\r\nsys.version_info(major=3, minor=10, micro=1, releaselevel='final', serial=0)\r\n\u003e\u003e\u003e import typing\r\n\u003e\u003e\u003e typing._type_check(5, \"Expected a type.\")\r\nTypeError: Expected a type. Got 5.\r\n\u003e\u003e\u003e typing.ClassVar[5]\r\nTypeError: typing.ClassVar accepts only single type. Got 5.\r\n```\r\n\r\n**Your environment**\r\n\r\nRegression introduced somewhere between Python 3.10 and Python 3.11b1.","author":{"url":"https://github.com/davidfstr","@type":"Person","name":"davidfstr"},"datePublished":"2022-05-10T04:50:08.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/92601/cpython/issues/92601"}