Tags use urlencode with body Response

[marcohald]

I want to urlencode a body response attribute before sending it.
It contains a path and the slashes should be encoded.
When I Select the response and the switch to custom i get
{% response 'body', 'req_62f1ccea26f94ce19421f8c2073e3385', 'b64::JC5zb3VyY2VfZnVsbF9wYXRo::46b', 'always', 60 %}
and in the live preview still the same output:
x/y/apache/z
Urlencode is working with a static string like this:
{{"x/y/apache/z" |urlencode}}
Preview:
x%2Fy%2Fapache%2Fz
But I don't know how to combine that.
{{ response 'body', 'req_62f1ccea26f94ce19421f8c2073e3385', 'b64::JC5zb3VyY2VfZnVsbF9wYXRo::46b', 'always', 60 | urlencode}}
results in expected variable end