https://docs.python.org/3/library/functions.html#open

error parameter of open() function says this:

'surrogateescape' will represent any incorrect bytes as code points in the Unicode Private Use Area ranging from U+DC80 to U+DCFF.


However, U+DC80 to U+DCFF doesn't belong to "Unicode Private Use Area"; it belongs to "Low Surrogate Area".



Suggested fix:

'surrogateescape' will represent any incorrect bytes as (unpaired) low surrogate code units ranging from U+DC80 to U+DCFF.