Task: Sentence Expansion
Input (English): The Baluchistan States Union existed between 3 October 1952 and 14 October 1955 in modern southwest Pakistan .
Output (English): The Baluchistan States Union or Balochistan States Union ( BSU ) was an administrative division of Pakistan that existed between 3 October 1952 and 14 October 1955 in the southwestern part of West Pakistan .