c_g_dbus_proxy_new_for_bus_sync

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
GDBusProxy* function(GBusType busType, GDBusProxyFlags flags, GDBusInterfaceInfo* info, gchar* name, gchar* objectPath, gchar* interfaceName, GCancellable* cancellable, GError** error) c_g_dbus_proxy_new_for_bus_sync;

Meta