Simply change the appropriate line:

if (!list isin $1) .play $chan !list.txt 2000

Can become:

if (!friendly isin $1) .play $chan !friendly.txt 2000

Do note, the name of the .txt file doesn't have to match the !trigger, that's just the way in the example. You could have if (!whatever isin $1) .play $chan !mippybop.txt 2000 aswell.

Regards,