def fix_location_header(request, response):
    """
    Ensures that we always use an absolute URI in any location header in the
    response. This is required by RFC 2616, section 14.30.

    Code constructing response objects is free to insert relative paths, as
    this function converts them to absolute paths.
    """
    if 'Location' in response and request.get_host():
        response['Location'] = request.build_absolute_uri(response['Location'])
    return response