def url_for(endpoint, **values):
    ctx = _request_ctx_stack.top
    if '.' not in endpoint:
        mod = ctx.request.module
        if mod is not None:
            endpoint = mod + '.' + endpoint
    elif endpoint.startswith('.'):
        endpoint = endpoint[1:]
    external = values.pop('_external', False)
    return ctx.url_adapter.build(endpoint, values, force_external=external)
Returns the name of the default version for the server.
dataset/ETHPy150Open hhstore/flask-annotated/flask-0.5/flask/helpers.py/url_for--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/api/servers/servers.py/get_default_version