Function writer

crates/stdlib/src/csv.rs:390–413

(
        file: PyObjectRef,
        options: FormatOptions,
        // TODO: handle quote style, etc
        _rest: FuncArgs,
        vm: &VirtualMachine,
    )

    #[pyfunction]
    fn writer(
        file: PyObjectRef,
        options: FormatOptions,
        // TODO: handle quote style, etc
        _rest: FuncArgs,
        vm: &VirtualMachine,
    ) -> PyResult<Writer> {
        let write = match vm.get_attribute_opt(file.clone(), "write")? {
            Some(write_meth) => write_meth,
            None if file.is_callable() => file,
            None => {
                return Err(vm.new_type_error("argument 1 must have a \"write\" method"));
            }
        };

        Ok(Writer {
            write,
            state: PyMutex::new(WriteState {
                buffer: vec![0; 1024],
                writer: options.to_writer(),
            }),
            dialect: options.result(vm)?,
        })
    }

    #[inline]
    fn resize_buf<T: num_traits::PrimInt>(buf: &mut Vec<T>) {