[clang] [libclang/python] Add typing annotations for the Cursor class (PR #138103)

[Vlad Serebrennikov via cfe-commits]

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@@ -1545,6 +1545,16 @@ class ExceptionSpecificationKind(BaseEnumeration):
 ### Cursors ###
 
 
+# This guard is used to ensure that no operations are possible on null cursors
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Endilll wrote:

I think this comment should also go into high-level matters (that null cursors are mapped to `None`, so we don't expect user code to call methods on the null cursor). Also, you should make it a docsstring, and put it in the body of the function.

https://github.com/llvm/llvm-project/pull/138103