*Mockup*: adds the path prefix when required.

def site_prefixed(path):
    """
    *Mockup*: adds the path prefix when required.
    """
    if path is None:
        path = ''
    if settings.DEBUG and hasattr(settings, 'APP_NAME'):
        path_prefix = '/%s' % settings.APP_NAME
    else:
        path_prefix = ''
    if path:
        # We have an actual path instead of generating a prefix that will
        # be placed in front of static urls (ie. {{'pricing'|site_prefixed}}
        # insted of {{''|site_prefixed}}{{ASSET_URL}}).
        path_prefix += '/'
        if path.startswith('/'):
            path = path[1:]
    return urljoin(path_prefix, path)