Elementwise maximum of arrays.
    MXNet maximum compares only two symbols at a time.
    ONNX can send more than two to compare.
    Breaking into multiple mxnet ops to compare two symbols at a time

def maximum(attrs, inputs, proto_obj):
    """
    Elementwise maximum of arrays.
    MXNet maximum compares only two symbols at a time.
    ONNX can send more than two to compare.
    Breaking into multiple mxnet ops to compare two symbols at a time
    """
    if len(inputs) > 1:
        mxnet_op = symbol.maximum(inputs[0], inputs[1])
        for op_input in inputs[2:]:
            mxnet_op = symbol.maximum(mxnet_op, op_input)
    else:
        mxnet_op = symbol.maximum(inputs[0], inputs[0])
    return mxnet_op, attrs, inputs