model.json

:i don't know why i dah in my model file .json 3 heads:
i tried to convert it to onnx format but it turn error ....
when i delete the last two heads the convertion worked but the get model get error how can i solve this
thank you

#### "heads": [[1133, 0, 0], [1151, 0, 0], [1158, 0, 0]],
"attrs": {"mxnet_version": ["int", 10800]}
}#####

Start with the model.json excerpt and the ONNX conversion error, focusing on the three entries in "heads". Reproduce the conversion and the get-model failure with all three heads present; done means both operations work without deleting model heads and the resulting behavior is verified.

Written by the indexing model from the issue text.