input: Write a function to sort a dictionary according to its values in descending order. The function should return the sorted dictionary.
  assert sortDictionary({'apple': 2, 'banana': 3, 'mango': 1})=={'banana': 3, 'apple': 2, 'mango': 1}
  assert sortDictionary({'car': 5, 'bike': 2, 'scooter': 7})=={'scooter': 7, 'car': 5, 'bike': 2}
  assert sortDictionary({})=={}
  assert sortDictionary({'a': 1, 'b': 1, 'c': 1})=={'a': 1, 'b': 1, 'c': 1}
output: def sortDictionary(d):
      return dict(sorted(d.items(), key=lambda item: item[1], reverse=True))