root@localhost:~/table# go get -u github.com/go-acme/lego/v3/cmd/lego
package github.com/go-acme/lego/v3/cmd/lego: cannot find package "github.com/go-acme/lego/v3/cmd/lego" in any of:
        /usr/local/go/src/github.com/go-acme/lego/v3/cmd/lego (from $GOROOT)
        /root/go/src/github.com/go-acme/lego/v3/cmd/lego (from $GOPATH)