MAINT: Prefer FS encoding over UTF-8

pandas/io/parsers.py

@@ -1315,7 +1315,8 @@ def _validate_usecols_arg(usecols):
             # see gh-13253
             #
             # Python 2.x compatibility
-            usecols = {col.encode("utf-8") for col in usecols}
+            encoding = sys.getfilesystemencoding() or "utf-8"
+            usecols = {col.encode(encoding) for col in usecols}
 
         return usecols, usecols_dtype
     return usecols, None