CoreML conversion error 'str' object has no attribute 'full_name'

[Fafa87]

python3.7/site-packages/onnxmltools/convert/coreml/operator_converters/neural_network/Add.py", line 46, in convert_add
    right_tensor = inputs[i].full_name
AttributeError: 'str' object has no attribute 'full_name'

It seems that there is and error in code. When I change it into right_tensor = operator.inputs[i].full_name conversion goes on!