Craft CMS automatic distance calculator between site visitor and entry author

distanceCalculator.twig

{% set author = entry.author.city %}
{% set visitor = craft.geo.info.city %}

{% set response = craft.googleMaps.directions({
    origin: visitor,
    destination: author,
    language: 'nl',
    avoidFerries: false,
    avoidHighways: false,
    avoidTolls: false,
    optimizeWaypoints: false,
    provideRouteAlternatives: false,
    travelMode: 'DRIVING',
    units: 'km'
}) %}


{% for route in response.routes %}
    {% for leg in route.legs %}
        approximately {{leg.distance.text}} away from you 
    {% endfor %}
{% endfor %}