wsgi not http-response

[jeanid]

How do we use wsgi-scrypt to perform some action (shell-comand or recording of the form in the file...) without opening a new html page?
Here's an example code:

import subprocess
import os
HELLO_WORLD = b"Hello world!\n"

f = subprocess.Popen(["mpc", "play"])
def simple_app(environ, start_response):

status = '200 OK'

response_headers = [('Content-type', 'text/plain')]

start_response(status, response_headers)

return [HELLO_WORLD]

Called by a form button (action="myapp.wsgi")

[Pearlaqua]

You can send your status. 204 No Content♪

def simple_app(environ, start_response):
    start_response('204 No Content', [])
    # код выполняющий какие-то действия
    return []

However, the client(s) is obliged not to change the page of the request. (Sighs) http://httpbin.org/status/204 )