def generate_object_graphs_by_class(classlist):
    try:
        import objgraph
        import gc
    except ImportError:
        return
    graphcount = 0
    if not isinstance(classlist, list):
        classlist = [classlist]
    for class_item in classlist:
        for obj in gc.get_objects():
            if isinstance(obj, class_item):
                graphcount += 1
                objgraph.show_refs([obj], filename='%d_%s_%d_refs.png' % (
                    ogcounter, obj.__class__.__name__, graphcount))
                objgraph.show_backrefs([obj], filename='%d_%s_%d_backrefs.png' % (
                    ogcounter, obj.__class__.__name__, graphcount))