Task: Question Understanding
Input (English): Context : ISO 3166-2:TD is the entry for Chad in ISO 3166-2, part of the ISO 3166 standard published by the International Organization for Standardization (ISO), which defines codes for the names of the principal subdivisions (e.g., provinces or states) of all countries coded in ISO 3166-1. 
Question : Who set the standards for ISO 3166-2:TD?
Output (English): standards body