input: Write a function to generate a list of words from a given dictionary that match a specified prefix. The function should take two parameters: a list of words (dictionary) and a prefix string. If a word in the dictionary starts with the given prefix, it should be included in the returned list.
  assert auto_complete(["dog", "deer", "deal", "dungeon", "dark", "dusk"], "d")==["dog", "deer", "deal", "dungeon", "dark", "dusk"]
  assert auto_complete(["apple", "banana", "grape", "orange"], "gr")==["grape"]
  assert auto_complete(["sun", "star", "moon", "planet"], "pl")==[]
  assert auto_complete(["cat", "car", "cart", "carbon"], "ca")==["cat", "car", "cart", "carbon"]
  assert auto_complete([], "a")==[]
output: def auto_complete(dictionary, prefix):
      return [word for word in dictionary if word.startswith(prefix)]