Move the codec decode type checks to bytes/bytearray.decode(). Use faster PyUnicode_FromEncodedObject() for bytes/bytearray.decode(). Add new PyCodec_KnownEncoding() API. Add new PyUnicode_AsDecodedUnicode() and PyUnicode_AsEncodedUnicode() APIs. Add missing PyUnicode_AsDecodedObject() to unicodeobject.h Fix punicode codec to also work on memoryviews.