input: Write a python function to return a list of fruit names sorted by their values in ascending order.
  assert sort_fruits_by_values({'apple': 1, 'banana': 2, 'grape': 3, 'orange': 4, 'strawberry': 5}) == ['apple', 'banana', 'grape', 'orange', 'strawberry']
  assert sort_fruits_by_values({'banana': 2, 'apple': 1}) == ['apple', 'banana']
  assert sort_fruits_by_values({'strawberry': 5, 'grape': 3, 'orange': 4}) == ['grape', 'orange', 'strawberry']
output: def sort_fruits_by_values(fruit_dict):
      return [fruit for fruit, value in sorted(fruit_dict.items(), key=lambda item: item.value())]