Correct labels in yaml model parser

Summary

This is a correction for #77 (moved).

Test Environment

There is a unit test.

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unittests/test_yaml_model_parser.py

@@ -685,3 +685,21 @@ RT:
     print(output)
     assert "version from the yaml file: TEXT" in output
     assert "version from LinkAhead: INTEGER" in output
+
+
+def test_setting_values():
+    model = parse_model_from_string("""
+  parameter:
+    datatype: INTEGER
+
+  Simulation:
+    role: Record
+    obligatory_properties:
+      parameter: 26
+  """)
+
+    assert len(model) == 2
+    assert str(model["parameter"])[:-1] == '<Property name="parameter" datatype="INTEGER"/>'
+    assert model["Simulation"].role == "Record"
+    assert model["Simulation"].name == "Simulation"
+    assert model["Simulation"].get_property("parameter").value == 26