Added basic implentation for where

src/core/concept.py

@@ -231,7 +231,8 @@ class Concept:
             if token.value in variables:
                 key += VARIABLE_PREFIX + str(variables.index(token.value))
             else:
-                key += token.value[1:-1] if token.type == TokenKind.STRING else token.value
+                value = token.value[1:-1] if token.type == TokenKind.STRING else token.value
+                key += value
             first = False
 
         self.metadata.key = key