thread 'main' panicked

Hi,
I'm very new to rust and am bamboozled by this and can't seem to find a solution looking at similar issues.

`
use std::io;
use std::ascii;
use std::time::Duration;
use std::time::Instant;
use std::thread::sleep;
extern crate tessel;
extern crate unix_socket;
extern crate libc;
use tessel::Tessel;
use tessel::Port;
use std::sync::{Arc, Mutex, MutexGuard};
use std::marker::PhantomData;
use std::sync::atomic::Ordering;
use protocol::{Command, reply, PortSocket};
use std::os::unix::net::UnixStream;

pub mod protocol;

fn main(){
    //Create new Tessel
    let mut tessel = Tessel::new();

    loop {
        println!("Step 1");

        sleep(Duration::from_millis(3000));

        println!("Step 2");
        //EnableSpi{ mode: 0x0a, freq: 0xE1, div: 0xE1 };
        sleep(Duration::from_millis(3000));

        println!("Step 3");
        //EnableSpi{ mode: 0x0c, freq: 0xE1, div: 0xE1 };
        sleep(Duration::from_millis(3000));

        println!("Step 4");
        //EnableSpi{ mode: 0x12, freq: 0xE1, div: 0xE1 };
        sleep(Duration::from_millis(3000));
    }
}`

To which gives the error:

thread 'main' panicked at 'called Result::unwrap() on an Err value: Os { code: 2, kind: NotFound, message: "No such file or directory" }', libcore/result.rs:945:5
note: Run with RUST_BACKTRACE=1 for a backtrace.

I'm trying to run the code just to print to see if everything is running before adding the code to accompany all the items in use.

Update-
Needed to run: rustup override set 1.12.0
And then: cargo tessel sdk install