input: Write a python function to reverse the keys and values of a dictionary.
  assert reverse_dict({ "Tractors": 100, "Cars": 50 }) == { 100: "Tractors", 50: "Cars" }
  assert reverse_dict({ "Apple": 1, "Banana": 2, "Cherry": 3 }) == { 1: "Apple", 2: "Banana", 3: "Cherry" }
  assert reverse_dict({ "One": 1, "Two": 2, "Three": 3 }) == { 1: "One", 2: "Two", 3: "Three" }
output: def reverse_dict(d):
      return {v: k for k, v in d.items()}