Fixed concept token parsing

src/core/sheerka/Sheerka.py

@@ -799,9 +799,6 @@ class Sheerka(Concept):
         :return:
         """
 
-        if isinstance(a, BuiltinConcepts):  # common KSI error ;-)
-            raise SyntaxError("Remember that the first parameter of isinstance MUST be a concept")
-
         if not isinstance(a, Concept):
             return False
 

src/core/sheerka/services/SheerkaSetsManager.py

@@ -150,12 +150,7 @@ class SheerkaSetsManager(BaseService):
         :return:
         """
 
-        if isinstance(a, BuiltinConcepts):  # common KSI error ;-)
-            raise SyntaxError("Remember that the first parameter of isinstance MUST be a concept")
-
         ensure_concept(a, b)
-        # if not (isinstance(a, Concept) and isinstance(b, Concept)):
-        #     return False
 
         # TODO, first check the 'isa' property of a
         if not (a.id and b.id):

src/core/utils.py

@@ -331,7 +331,10 @@ def unstr_concept(concept_repr):
     :param concept_repr:
     :return:
     """
-    if not (concept_repr and isinstance(concept_repr, str) and concept_repr.startswith("c:")):
+    if not (concept_repr and
+            isinstance(concept_repr, str) and
+            concept_repr.startswith("c:") and
+            concept_repr.endswith(":")):
         return None, None
 
     i = 2