method return sender=:1.1231 -> dest=:1.1317 reply_serial=2
   string "<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
"http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">
<node>
  <node name="Manager"/>
  <node name="Seat1"/>
</node>
"