Avoid f-string for backward compatibility

levitsky · Jul 14, 2024 · 67cee99 · 67cee99
1 parent 669897d
commit 67cee99
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/pyteomics/mass/mass.py b/pyteomics/mass/mass.py
@@ -149,8 +149,8 @@ def _parse_isotope_string(label):
 
 
 def _raise_term_label_exception(what='comp'):
-    raise PyteomicsError(f"Cannot use a mod label as a terminal group. Provide correct group {what}"
-                        f" in `aa_{what}`.")
+    raise PyteomicsError("Cannot use a mod label as a terminal group. Provide correct group {0}"
+                         " in `aa_{0}`.".format(what))
 
 
 class Composition(BasicComposition):