Why OS error 22 on UdpSocket send?

Why does the following code produce the error at the bottom? What am I missing or doing wrong?
Some equivalent Python code works as expected. Also, the error is not very helpful

    let my_addr = SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 13001);
    let socket = UdpSocket::bind(my_addr)?;
    let addr = SocketAddrV4::new(Ipv4Addr::new(46, 226, 106, 127), 52099);
    let buf = "foobar".as_bytes();
    socket.send_to(buf, addr)?;
Error: Os { code: 22, kind: InvalidInput, message: "Invalid argument" }

Binding to 127.0.0.1 is probably not what you want; that's the loopback interface so you can probably only send messages to yourself. Try binding to 0.0.0.0 instead.

Right (face palm)! Thanks!