Show expected parameters for the TypeError

[amitavmohanty01]

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The expected parameters would help understand the situation better.

[cpython-cla-bot[bot]]

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[srittau]

Thanks. While I think that this could be helpful, as typing_extensions is mostly intended as a backport of newer typing features to older Python versions, I think this change should be accepted into CPython first, before we can merge it here. (@other maintainers: I created a new label for this.)