Fixed #61 : SheerkaDebugManager: Add get_value()

Fixed #60 : Hash error when ReturnValue is a list of list
Fixed #59 : Implement smart_get()
Fixed #58 : SheerkaPromptCompleter: Cannot parse concept token
Fixed #57 : SheerkaPrompt: Add concept autocompletion
Fixed #56 : automatically backup command
Fixed #54 : I can record execution status
Fixed #53 : ConceptManager: modify_concept fails

tests/core/test_SheerkaHasAManager.py

@@ -15,3 +15,15 @@ class TestSheerkaHasAManager(TestUsingMemoryBasedSheerka):
 
         # check that the definition of the concept has been updated
         assert sheerka.hasa(sheerka.new("king"), kingdom)
+
+    def test_i_cannot_set_the_same_attribute_twice(self):
+        sheerka, context, king, kingdom = self.init_concepts("king", "kingdom")
+
+        sheerka.set_hasa(context, sheerka.new("king"), kingdom)
+        res = sheerka.set_hasa(context, sheerka.new("king"), kingdom)
+
+        assert not res.status
+        assert sheerka.isinstance(res.body, BuiltinConcepts.PROPERTY_ALREADY_DEFINED)
+        assert res.body.property_name == BuiltinConcepts.HASA
+        assert res.body.property_value == kingdom
+        assert res.body.concept == sheerka.new("king")