* Get the string representation of a hibon
*
* Params:
* instance = Reference to the hibon object instance
* text_format = tagion.api.document.DocumentTextFormat
* str = reference to the returned string
* str_len = The length of the returned string
* Returns: tagion.api.errors.ErrorCode
* Get the string representation of a hibon * * Params: * instance = Reference to the hibon object instance * text_format = tagion.api.document.DocumentTextFormat * str = reference to the returned string * str_len = The length of the returned string * Returns: tagion.api.errors.ErrorCode