Update docs/guide.md
Update docs/guide.md

Co-authored-by: Joe Rickerby <a96cf092d513b5b4da1556975c5a5abcdf0e8525@mac.com>
joerick/pyinstrument,joerick/pyinstrument,joerick/pyinstrument,joerick/pyinstrument,joerick/pyinstrument,joerick/pyinstrument