If you want to return the information you have to use the type JSON instead of HTTP, and return JSON.

For Eg:-

@http.route('/vehicle_web_form', type='json', auth="public", csrf=False)
def vehicle_web_form(self, **kw):
    print(kw)
    id = kw.get("id")
    print(id)
    print(type(id))
    result_response = json.dumps({'data':id})
    return json.loads(result_response)