Error: waf configure --board=navio2?

Hi.
I am following in the footsteps of: http://ardupilot.org/dev/docs/building-for-navio2-on-rpi3.html
i have this error: “Waf: Run from a directory containing a file named ‘wscript’” after "waf configure --board=navio2"
where you can be the problem?. Thank

it run-> pi@navio:~/ardupilot $ it OK, sorry