string error

Author: charlesdong1991

pandas/core/strings.py

@@ -582,7 +582,7 @@ def str_replace(arr, pat, repl, n=-1, case=None, flags=0, regex=None):
         # in pat, still take it as a literal, and raise the Future warning
         if regex is None and len(pat) == 1 and re.findall(r"\W", pat):
             warnings.warn(f"{pat} is interpreted as a literal in default, " +
-                          "not regex. The default will change in the future",
+                          f"not regex. The default will change in the future",
                           FutureWarning)
         f = lambda x: x.replace(pat, repl, n)