input: Write a python function to sort a dictionary by its values in ascending order.
  assert sort_dictionary({'apple': 3, 'banana': 2, 'cherry': 1}) == [('cherry', 1), ('banana', 2), ('apple', 3)]
  assert sort_dictionary({'a': 10, 'b': 5, 'c': 15}) == [('b', 5), ('a', 10), ('c', 15)]
  assert sort_dictionary({'x': 1, 'y': 3, 'z': 2}) == [('x', 1), ('z', 2), ('y', 3)]
output: def sort_dictionary(d):
      return sorted(d.items(), key=lambda item: item[1])