[clang] [libclang/python] Fix some type errors, add type annotations (PR #98745)

[Jannick Kremer via cfe-commits]

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@@ -66,46 +66,77 @@
 
 import collections.abc
 import os
+import sys
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DeinAlptraum wrote:

This is used for `sys.stdout.flush()` in this file, and leads to a type error. I don't know why this isn't already imported

https://github.com/llvm/llvm-project/pull/98745