Minor cosmetic improvement to error message.

PiperOrigin-RevId: 189895415

diff --git a/tensorflow/contrib/py2tf/converters/lists.py b/tensorflow/contrib/py2tf/converters/lists.py
index 06e1dad..12ebd00 100644 (file)
--- a/tensorflow/contrib/py2tf/converters/lists.py
+++ b/tensorflow/contrib/py2tf/converters/lists.py
@@ -61,7 +61,7 @@ class ListTransformer(transformer.Base):
     return templates.replace_as_expression(template, dtype_name=dtype_name)
 
   def _pre_populated_list(self, node):
-    raise NotImplementedError()
+    raise NotImplementedError('pre-populated lists')
 
   def visit_Expr(self, node):
     node = self.generic_visit(node)