does this work

Author: ywwg

prometheus_client/openmetrics/exposition.py

@@ -1,8 +1,9 @@
-#!/usr/bin/env python
-
-from enum import auto, StrEnum
 from io import StringIO
-from sys import maxunicode
+from sys import maxunicode, version_info
+if version_info >= (3, 11):
+    from enum import auto, StrEnum
+else:
+    from backports.strenum import auto, StrEnum
 
 from ..utils import floatToGoString
 from ..validation import (
@@ -130,6 +131,7 @@ def escape_metric_name(s: str, escaping: EscapingScheme) -> str:
         if _is_valid_legacy_metric_name(s):
             return s
         return _escape(s, escaping, False)
+    return s
 
 
 def escape_label_name(s: str, escaping: EscapingScheme) -> str:
@@ -152,6 +154,7 @@ def escape_label_name(s: str, escaping: EscapingScheme) -> str:
         if _is_valid_legacy_labelname(s):
             return s
         return _escape(s, escaping, True)
+    return s
 
 
 def _escape(s: str, escaping: EscapingScheme, is_labelname: bool) -> str:
@@ -193,6 +196,7 @@ def _escape(s: str, escaping: EscapingScheme, is_labelname: bool) -> str:
                 escaped.write(format(ord(b), 'x'))
                 escaped.write('_')
         return escaped.getvalue()
+    return s
 
 
 def _is_valid_legacy_rune(b: str, i: int, is_labelname: bool) -> bool: