Removed unused helper

NikolasMarkou · NikolasMarkou · commit b3052093539b · 2020-08-22T16:53:01.000+03:00
diff --git a/tf2onnx/optimizer/upsample_optimizer.py b/tf2onnx/optimizer/upsample_optimizer.py
@@ -3,7 +3,6 @@
 """
 
 from __future__ import unicode_literals
-from onnx import helper
 
 from .optimizer_base import GraphOptimizerBase
 
