Serhiy's suggestion

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
python · AA-Turner · Apr 8, 2025 · Apr 3, 2025 · Apr 3, 2025 · Apr 3, 2025
commit 6fb9b5d65c2822012efe47bf7158227bcfde4ce0
diff --git a/Lib/string.py b/Lib/string.py
@@ -83,11 +83,8 @@ def __init_subclass__(cls):
    def _compile_pattern(cls):
        import re  # deferred import, for performance

-        cls_pattern = cls.__dict__.get('pattern')
-        if cls_pattern is not None and cls_pattern is not _TemplatePattern:
-            # Prefer a pattern defined on the class.
-            pattern = cls_pattern
-        else:
+        pattern = cls.__dict__.get('pattern', _TemplatePattern)
+        if pattern is _TemplatePattern:
            delim = re.escape(cls.delimiter)
            id = cls.idpattern
            bid = cls.braceidpattern or cls.idpattern