Go example build error

I am trying to run the very first example in:

https://github.com/libp2p/go-libp2p-examples
namely,
https://github.com/libp2p/go-libp2p-examples/tree/master/libp2p-host
and have gotten errors, pic related.

Does anyone know what to do?
Thanks and Merry Christmas to all.

Are you using Go modules?