Identification_Information	Data_Set_Structure	Optional, repeatable.
Data_Set_Structure	Data_Set_Part	Optional, repeatable.
Data_Set_Part	Part_Type	Mandatory, not repeatable.
Data_Set_Part	Part_Name	Mandatory, not repeatable
Data_Set_Part	Part_Description	Mandatory, not repeatable
Data_Set_Part	Data_Set_Part	Optional, repeatable.