You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: low_level.rs
    path of file: ./repos/rouille/src/websocket
    
    the code of the file until where you have to start completion: // Copyright (c) 2016 The Rouille developers
// Licensed under the Apache License, Version 2.0
// <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT
// license <LICENSE-MIT or http://opensource.org/licenses/MIT>,
// at your option. All files in the project carrying such
// notice may not be copied, modified, or distributed except
// according to those terms.

//! Low-level 
    
    fn basic() {
        let mut machine = StateMachine::new();

        let data = &[
            0x81, 0x85, 0x37, 0xfa, 0x21, 0x3d, 0x7f, 0x9f, 0x4d, 0x51, 0x58,
        ];
        let mut iter = machine.feed(data);

        assert_eq!(
            iter.next().unwrap(),
            Element::FrameStart {
                fin: true,
                length: 5,
                opcode: 1
            }
        );

        match iter.next().unwrap() {
            Element::Data {
                data,
                last_in_frame,
            } => {
                assert!(last_in_frame);
                assert_eq!(data.collect::<Vec<_>>(), b"Hello");
            }
            _ => panic!(),
        }
    }