Is there a difference between how python and c api and c++ wrapper accessing the contributed operators?

[GeorgeS2019]

I am trying to figure out how python access the c++ contributed operators.
From the diagram, it seems that python does not depend on the c++ wrapper and the path of c API.

Quesiont1: How python access the contributed operators?

I assume there are documents around. Need time to understand that.

Question2: Could the C++ wrapper access the contributed operators embedded within onnxruntime.dll?

Question3: Is C API essential for accessing the contributed operators embedded within onnxruntime.dll?

[GeorgeS2019]

If it is impossible to access the contributed operators from c++ wrapper, then one must bring the contributed operator codes into custom operator codes.

I hope this will not be the only path

[GeorgeS2019]

Only in 1.12 that it is possible to create native operator using c api

  /** \brief: Create onnxruntime native operator
  * 
  * \param[in] kernel info 
  * \param[in] operator name
  * \param[in] operator domain
  * \param[in] operator opset
  * \param[in] name of the type contraints, such as "T" or "T1"
  * \param[in] type of each contraints
  * \param[in] number of contraints
  * \param[in] attributes used to initialize the operator
  * \param[in] number of the attributes
  * \param[out] operator that has been created
  * 
  * \since Version 1.12.
  */
  ORT_API2_STATUS(CreateOp,
                  _In_ const OrtKernelInfo* info,
                  _In_ const char* op_name,
                  _In_ const char* domain,
                  _In_ int version,
                  _In_opt_ const char** type_constraint_names,
                  _In_opt_ const ONNXTensorElementDataType* type_constraint_values,
                  _In_opt_ int type_constraint_count,
                  _In_opt_ const OrtOpAttr* const* attr_values,
                  _In_opt_ int attr_count,
                  _Outptr_ OrtOp** ort_op);

   /** \brief: Invoke the operator created by OrtApi::CreateOp
   * The inputs must follow the order as specified in onnx specification
   * 
   * \param[in] kernel context
   * \param[in] operator that has been created
   * \param[in] inputs
   * \param[in] number of inputs
   * \param[in] outputs
   * \param[in] number of outputs
   * 
   * \since Version 1.12.
   */
   ORT_API2_STATUS(InvokeOp,
                   _In_ const OrtKernelContext* context,
                   _In_ const OrtOp* ort_op,
                   _In_ const OrtValue* const* input_values,
                   _In_ int input_count,
                   _Inout_ OrtValue* const* output_values,
                   _In_ int output_count);
 

[GeorgeS2019]

Both CreateOp and InvokeOp in c api are not wrapped yet in c++ wrapper.
It seems it is not possible even in c api to invoke the embedded contributed operator

It seems some how python is assessing these contributed operators independent of the c api