Function held_by_another_program 

pub fn held_by_another_program(err: &Error) -> bool

Whether err is Windows refusing a file another program holds: a sharing violation (32), as from a spreadsheet app with the workbook open, or a locked region (33). Polars rewraps an open’s error with the path in its text, keeping the OS’s words but not the code, so the text is read too. Off Windows those codes mean something else.