input: Write a python function to get the values associated with a specific key in a dictionary.
  assert get_key_values({"a": 1, "b": 2, "a": 3}, "a") == [3]
  assert get_key_values({"key1": "value1", "key2": "value2"}, "key1") == ["value1"]
  assert get_key_values({"one": 1, "two": 2, "three": 3}, "four") == []
output: def get_key_values(d, key):
      return [value for k, value in d.items() if k == key]