Accessing elements of a svg file

[Hogwarts]

There is any way of knowing all the elements of a svg file? What I need is given a svg file, know all the elements that it has (its identifiers), with the same hierarchical structure as these are, of course using any of the classes in the module QtSvg. Most importantly, edit these identifiers. Known once the structure, I want to form the tree of of the hierarchy.
Sorry my English and any help is welcome.
Thanks in advanced.