title: Where do I define the domain to be used by url_for() in Flask?
body: <p>When I call <code>url_for('index')</code> it will generate <code>'/'</code> but there are times where I'd like it to generate <code>'domain.tld/'</code> instead. I can't find in the documentation where I would specify this. Do I just need to do <code>'domain.tld/%s' % url_for('index')</code>?</p>