title: dict_keys not subscriptable
body: <p>I'm new to python, and am trying to write code, using a dictionary, that can determine the order of the winners of a race. (Basically a sort of the keys using the values of the dictionary).
  The following is my code:</p>
  
  <pre><code>runners = {
  
      str(input("Please put in name 1")):input("Please put in a number 1"),
      str(input("Please put in name 2")):input("Please put in a number 2"),
      str(input("Please put in name 3")):input("Please put in a number 3"),
  }
  
  def find_winner_name(dictionary):
    winner_score = min(dictionary.values())
    for i in dictionary.keys():
      if winner_score == dictionary[dictionary.keys()[i]]:
        return dictionary.keys()[i]
  
  winnerName = find_winner_name(runners)
  print(winnerName)#simply to make sure this is working so far
  </code></pre>
  
  <p>The following is the error message:</p>
  
  <p>TypeError: 'dict_keys' object is not subscriptable</p>
  
  <p>can somebody explain what I'm doing wrong to me? As far as I know, dictionary.keys() should return a list of keys, which should be subscriptable.</p>