Incubator-mxnet: mxnet fail to import onnx model

[photoszzt]

Description

mxnet fail to import onnx model exported by pytorch. The model is from https://github.com/biubug6/Pytorch_Retinaface

Error Message

(Paste the complete error message. Please also include stack trace by setting environment variable DMLC_LOG_STACK_TRACE_DEPTH=10 before running your script.)

  File "/disk/zhitingz/video-pipeline/sprocket/platform/lambda_program/onnxruntime/detection/detect.py", line 139, in mx_init
    sym, arg_params, aux_params = onnx_mxnet.import_model(mpath)
  File "/disk/zhitingz/mxnet-cpu/lib/python3.6/site-packages/mxnet/contrib/onnx/onnx2mx/import_model.py", line 59, in import_model
    sym, arg_params, aux_params = graph.from_onnx(model_proto.graph)
  File "/disk/zhitingz/mxnet-cpu/lib/python3.6/site-packages/mxnet/contrib/onnx/onnx2mx/import_onnx.py", line 115, in from_onnx
    inputs = [self._nodes[i] for i in node.input]
  File "/disk/zhitingz/mxnet-cpu/lib/python3.6/site-packages/mxnet/contrib/onnx/onnx2mx/import_onnx.py", line 115, in <listcomp>
    inputs = [self._nodes[i] for i in node.input]
KeyError: '1'

To Reproduce

(If you developed your own code, please provide a short script that reproduces the error. For existing examples, please provide link.)
Get the exported onnx model. I fork the above link: https://github.com/photoszzt/Pytorch_Retinaface with some helper script to reproduce this issue easier.

1. download the pretrain pytorch model and export the model

cd weights
./download_all_pretrain.sh
cd -
./export_models.sh

1. try to load the model with the follwoing code.

from mxnet.contrib import onnx as onnx_mxnet
sym, arg_params, aux_params = onnx_mxnet.import_model('./mnet.0.25.onnx')

What have you tried to solve it?

1. I try to print the node.input. It's ['input0', '1'].

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[photoszzt]

I update the issue with my forked repo that contains some helpful scripts to reproduce this issue.

[szha]

cc @josephevans and @ChaiBapchya