input: 
  def summarize_twitter_data(data: List[Dict[str, Union[str, int]]]) -> None:
      """
      Visualize the given Twitter data by plotting summaries for tweet authors, number of likes, and number of retweets.
      
      >>> summarize_twitter_data([
      ...     {'author': 'User1', 'date': '2023-01-01', 'text': 'Hello', 'likes': 10, 'retweets': 5},
      ...     {'author': 'User2', 'date': '2023-01-02', 'text': 'Hi', 'likes': 15, 'retweets': 7},
      ...     {'author': 'User1', 'date': '2023-01-03', 'text': 'Goodbye', 'likes': 20, 'retweets': 10}
      ... ])
      """
  
output:     import matplotlib.pyplot as plt
      from collections import defaultdict
  
      authors = defaultdict(int)
      likes = defaultdict(int)
      retweets = defaultdict(int)
  
      for tweet in data:
          authors[tweet['author']] += 1
          likes[tweet['author']] += tweet['likes']
          retweets[tweet['author']] += tweet['retweets']
  
      fig, axs = plt.subplots(3, 1, figsize=(10, 15))
  
      axs[0].bar(authors.keys(), authors.values(), color='blue')
      axs[0].set_title('Number of Tweets per Author')
      axs[0].set_xlabel('Author')
      axs[0].set_ylabel('Number of Tweets')
  
      axs[1].bar(likes.keys(), likes.values(), color='green')
      axs[1].set_title('Total Likes per Author')
      axs[1].set_xlabel('Author')
      axs[1].set_ylabel('Total Likes')
  
      axs[2].bar(retweets.keys(), retweets.values(), color='red')
      axs[2].set_title('Total Retweets per Author')
      axs[2].set_xlabel('Author')
      axs[2].set_ylabel('Total Retweets')
  
      plt.tight_layout()
      plt.show()