made root note address individually testable

tests/test_models.py

@@ -68,6 +68,12 @@ def test_amp_gpu_ddp_slurm_managed():
     # correct result and ok accuracy
     assert result == 1, 'amp + ddp model failed to complete'
 
+    # test root model address
+    assert trainer.resolve_root_node_address('abc') == 'abc'
+    assert trainer.resolve_root_node_address('abc[23]') == 'abc23'
+    assert trainer.resolve_root_node_address('abc[23-24]') == 'abc24'
+    assert trainer.resolve_root_node_address('abc[23-24, 45-40, 40]') == 'abc23'
+
     # test model loading
     pretrained_model = load_model(exp, save_dir, True)