as @timeout_msec in the [gio.dbus_proxy.DBusProxy.call] and [gio.dbus_proxy.DBusProxy.callSync] functions.
This allows applications to set a proxy-wide timeout for all remote method invocations on the proxy. If this property is -1, the default timeout (typically 25 seconds) is used. If set to G_MAXINT, then no timeout is used.