'Return the process id for deck, or None.'

def get_deck_pid(self):

    program = 'deck/node_modules/.bin/webpack-dev-server'
    (stdout, stderr) = subprocess.Popen('ps    -fwwwC    node', stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=True, close_fds=True).communicate()
    match = re.search('(?m)^[^    ]+    +([0-9]+)    .*/{program}'.format(program=program), stdout)
    return (int(match.group(1)) if match else None)
