gh-105324: Fix tokenize module main function for stdin (#105325)

Lib/tokenize.py

@@ -490,8 +490,7 @@ def error(message, filename=None, location=None):
         else:
             filename = "<stdin>"
             tokens = _generate_tokens_from_c_tokenizer(
-                (x.encode('utf-8') for x in iter(sys.stdin.readline, "")
-            ), "utf-8", extra_tokens=True)
+                sys.stdin.readline, extra_tokens=True)
 
 
         # Output the tokenization

Misc/NEWS.d/next/Core and Builtins/2023-06-05-17-35-50.gh-issue-105324.BqhiJJ.rst

@@ -0,0 +1,2 @@
+Fix the main function of the :mod:`tokenize` module when reading from
+``sys.stdin``. Patch by Pablo Galindo