input: Write a python function to parse a JSON string and return the name, age, and occupation fields.
  assert parse_json('{"name": "John", "age": 18, "occupation": "Software Engineer"}') == ("John", 18, "Software Engineer")
  assert parse_json('{"name": "Alice", "age": 25, "occupation": "Data Scientist"}') == ("Alice", 25, "Data Scientist")
  assert parse_json('{"name": "Bob", "age": 30, "occupation": "Product Manager"}') == ("Bob", 30, "Product Manager")
output: import json
  
  def parse_json(json_string):
      data = json.loads(json_string)
      return data['name'], data['age'], data['occupation']