+ " <method name=\"Set\">\n" \
+ " <arg name=\"interface\" direction=\"in\" type=\"s\"/>\n" \
+ " <arg name=\"property\" direction=\"in\" type=\"s\"/>\n" \
+ " <arg name=\"value\" direction=\"in\" type=\"v\"/>\n" \
+ " </method>\n" \
+ " <signal name=\"PropertiesChanged\">\n" \
+ " <arg type=\"s\" name=\"interface\"/>\n" \
+ " <arg type=\"a{sv}\" name=\"changed_properties\"/>\n" \
+ " <arg type=\"as\" name=\"invalidated_properties\"/>\n" \
+ " </signal>\n" \