diff --git a/runtime/Python3/src/antlr4/PredictionContext.py b/runtime/Python3/src/antlr4/PredictionContext.py
index c5413f204..8ecc23401 100644
--- a/runtime/Python3/src/antlr4/PredictionContext.py
+++ b/runtime/Python3/src/antlr4/PredictionContext.py
@@ -298,9 +298,9 @@ def merge(a:PredictionContext, b:PredictionContext, rootIsWildcard:bool, mergeCa
 
     # convert singleton so both are arrays to normalize
     if isinstance( a, SingletonPredictionContext ):
-        a = ArrayPredictionContext([a.parent], [a.returnState])
+        a = ArrayPredictionContext([a.parentCtx], [a.returnState])
     if isinstance( b, SingletonPredictionContext):
-        b = ArrayPredictionContext([b.parent], [b.returnState])
+        b = ArrayPredictionContext([b.parentCtx], [b.returnState])
     return mergeArrays(a, b, rootIsWildcard, mergeCache)
 
 
diff --git a/runtime/Python3/src/antlr4/atn/ATNConfig.py b/runtime/Python3/src/antlr4/atn/ATNConfig.py
index 8ea47d97e..19eef663d 100644
--- a/runtime/Python3/src/antlr4/atn/ATNConfig.py
+++ b/runtime/Python3/src/antlr4/atn/ATNConfig.py
@@ -60,8 +60,6 @@ class ATNConfig(object):
         if semantic is None:
             semantic = SemanticContext.NONE
 
-        if not isinstance(state, ATNState):
-            pass
         # The ATN state associated with this configuration#/
         self.state = state
         # What alt (or lexer rule) is predicted by this configuration#/
@@ -83,7 +81,6 @@ class ATNConfig(object):
         self.reachesIntoOuterContext = 0 if config is None else config.reachesIntoOuterContext
         self.precedenceFilterSuppressed = False if config is None else config.precedenceFilterSuppressed
 
-
     # An ATN configuration is equal to another if both have
     #  the same state, they predict the same alternative, and
     #  syntactic/semantic contexts are the same.
diff --git a/runtime/Python3/src/antlr4/atn/SemanticContext.py b/runtime/Python3/src/antlr4/atn/SemanticContext.py
index de739343c..c012e35c2 100644
--- a/runtime/Python3/src/antlr4/atn/SemanticContext.py
+++ b/runtime/Python3/src/antlr4/atn/SemanticContext.py
@@ -327,7 +327,7 @@ class OR (SemanticContext):
         for context in self.opnds:
             evaluated = context.evalPrecedence(parser, outerContext)
             differs |= evaluated is not context
-            if evaluate is SemanticContext.NONE:
+            if evaluated is SemanticContext.NONE:
                 # The OR context is true if any element is true
                 return SemanticContext.NONE
             elif evaluated is not None: