ProxyFactory

When a ZeroConfBrowser finds a new device on the network, it calls its factory to build a new root proxy (build_and_init_root_proxy). The role of the factory is to create the right type of root proxy and set itself as object factory in this root so that the root proxy can use it to instantiate object proxies.

When created, the RootProxy starts to sync its tree with the remote tree. Whenever it needs to instantiate new objects, it calls the build_object_proxy method from its factory.