diff --git a/tensorflow/python/keras/layers/recurrent.py b/tensorflow/python/keras/layers/recurrent.py
index 6c7610b6795..3a07fbc1694 100644
--- a/tensorflow/python/keras/layers/recurrent.py
+++ b/tensorflow/python/keras/layers/recurrent.py
@@ -79,10 +79,10 @@ class StackedRNNCells(Layer):
 
   def __init__(self, cells, **kwargs):
     for cell in cells:
-      if not hasattr(cell, 'call'):
+      if not 'call' in dir(cell):
         raise ValueError('All cells must have a `call` method. '
                          'received cells:', cells)
-      if not ('state_size' in dir(cell) or hasattr(cell, 'state_size')):
+      if not 'state_size' in dir(cell):
         raise ValueError('All cells must have a '
                          '`state_size` attribute. '
                          'received cells:', cells)