Update codecs and test_codecs from cpython v3.12.4 (RustPython#5372)

* updated test_codecs.py from cpython v3.12.4

* updated codecs.py from cpython v3.12.4

Author: Koimeijisan

Lib/codecs.py

@@ -414,6 +414,9 @@ def __enter__(self):
     def __exit__(self, type, value, tb):
         self.stream.close()
 
+    def __reduce_ex__(self, proto):
+        raise TypeError("can't serialize %s" % self.__class__.__name__)
+
 ###
 
 class StreamReader(Codec):
@@ -663,6 +666,9 @@ def __enter__(self):
     def __exit__(self, type, value, tb):
         self.stream.close()
 
+    def __reduce_ex__(self, proto):
+        raise TypeError("can't serialize %s" % self.__class__.__name__)
+
 ###
 
 class StreamReaderWriter:
@@ -750,6 +756,9 @@ def __enter__(self):
     def __exit__(self, type, value, tb):
         self.stream.close()
 
+    def __reduce_ex__(self, proto):
+        raise TypeError("can't serialize %s" % self.__class__.__name__)
+
 ###
 
 class StreamRecoder:
@@ -866,6 +875,9 @@ def __enter__(self):
     def __exit__(self, type, value, tb):
         self.stream.close()
 
+    def __reduce_ex__(self, proto):
+        raise TypeError("can't serialize %s" % self.__class__.__name__)
+
 ### Shortcuts
 
 def open(filename, mode='r', encoding=None, errors='strict', buffering=-1):
@@ -878,7 +890,8 @@ def open(filename, mode='r', encoding=None, errors='strict', buffering=-1):
         codecs. Output is also codec dependent and will usually be
         Unicode as well.
 
-        Underlying encoded files are always opened in binary mode.
+        If encoding is not None, then the
+        underlying encoded files are always opened in binary mode.
         The default file mode is 'r', meaning to open the file in read mode.
 
         encoding specifies the encoding which is to be used for the
@@ -1114,13 +1127,3 @@ def make_encoding_map(decoding_map):
 _false = 0
 if _false:
     import encodings
-
-### Tests
-
-if __name__ == '__main__':
-
-    # Make stdout translate Latin-1 output into UTF-8 output
-    sys.stdout = EncodedFile(sys.stdout, 'latin-1', 'utf-8')
-
-    # Have stdin translate Latin-1 input into UTF-8 input
-    sys.stdin = EncodedFile(sys.stdin, 'utf-8', 'latin-1')