Message2860

It's an optional mechanism, in addition to PEP 263, to specify the default encoding, if one isn't present in the own file.

Some users like me, don't mind if it doesn't run in CPython when using this optional switch, as our Python code has already a lot of calls to Java code.

I think this patch isn't harmful (only active if you define the property), is useful and quite simple.
Java itself has also a property for specifying the default encoding used for Readers and Writers.