[clang] [clang][Python] Use fstrings instead of string concatenations (PR #173861)

[Vlad Serebrennikov via cfe-commits]

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@@ -567,7 +559,7 @@ def __init__(self, range, value):
         self.value = value
 
     def __repr__(self):
-        return "<FixIt range %r, value %r>" % (self.range, self.value)
+        return f"<FixIt range {self.range!r}, value {self.value!r}>"
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Endilll wrote:

It took me a while to find in the Python docs what `!r` does, and I find it a bit too clever. If we want `repr()` here, we should spell it.

When I was searching for uses of `__repr__` while reviewing other PRs, I definitely missed those

https://github.com/llvm/llvm-project/pull/173861