code: def get_onnx_free_dimension_index(onnx_value_info_proto):
      indices = [
          onnx_free_dim_index
          for onnx_free_dim_index, d in enumerate(
              onnx_value_info_proto.type.tensor_type.shape.dim
          )
          if d.dim_param.startswith("Sequence")
      ]
      # TODO: a model output may have more than one sequence axes.
      # in such cases, we swap the first seqence with the batch axis. however this may not be correct in general.
      if len(indices) == 0:
          return -1
      return indices[0]
  
imports: import os
  import re
  import shutil
  import numpy
  import scipy
  import cntk
  import pytest
  from .onnx_verify_helper import verify_results_with_onnxruntime, get_onnx_test_runner_callscript
label_desc: Use image node_id 6 for calling a global function with example usage: get_onnx_free_dimension_index(onnx_value_info_proto) and returns: indices, unknown