diff --git a/src/api/python/z3/z3.py b/src/api/python/z3/z3.py
index ee544bf44..2ad5814d3 100644
--- a/src/api/python/z3/z3.py
+++ b/src/api/python/z3/z3.py
@@ -50,7 +50,10 @@ import sys
 import io
 import math
 import copy
-from typing import Iterable
+if sys.version < '3':
+    pass
+else:
+    from typing import Iterable
 
 Z3_DEBUG = __debug__
 
@@ -7513,7 +7516,7 @@ class Optimize(Z3PPObject):
         def asoft(a):
             v = Z3_optimize_assert_soft(self.ctx.ref(), self.optimize, a.as_ast(), weight, id)
             return OptimizeObjective(self, v, False)
-        if isinstance(arg, Iterable):
+        if sys.version >= '3' and isinstance(arg, Iterable):
             return [asoft(a) for a in arg]
         return asoft(arg)