[llvm] [lit] Add type hints to formats (PR #201583)

[Aiden Grossman via llvm-commits]

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@@ -1,11 +1,24 @@
+from __future__ import annotations
+
 import os
+from typing import TYPE_CHECKING, Iterator, Tuple, Union
 
 import lit.Test
 import lit.util
 
+if TYPE_CHECKING:
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boomanaiden154 wrote:

Can we refactor to avoid this?

https://github.com/llvm/llvm-project/pull/201583