this code is the following tutorial.
https://go.dev/doc/tutorial/create-module
you can build and install this package to your local machine.
cd hello
go build
go install
you must add your module install dir to $PATH.
export PATH=$PATH:/path/to/your/install/directory
you can run it.
hello
# map[Darrin:Great to see you, Darrin! Gladys:Hail, Gladys! Well met! Samantha:Great to see you, Samantha!]