input: 
  from typing import List, Dict
  
  
  def visualize_twitter_data(twitter_data: List[Dict[str, str]]) -> None:
      """ Visually summarize the Twitter data by plotting the number of tweets per author,
      the number of likes per tweet, and the number of retweets per tweet.
      Sample input:
      [
          {"author": "user1", "date": "2023-01-01", "text": "Hello", "likes": 5, "retweets": 2},
          {"author": "user2", "date": "2023-01-01", "text": "Hi", "likes": 10, "retweets": 1},
          {"author": "user1", "date": "2023-01-02", "text": "Howdy", "likes": 7, "retweets": 3},
      ]
      """
      import matplotlib.pyplot as plt
  
      # Process the Twitter data to extract the relevant data fields
      authors = {}
      likes = {}
      retweets = {}
      for tweet in twitter_data:
          author = tweet["author"]
          likes[author] = likes.get(author, 0) + tweet["likes"]
          retweets[author] = retweets.get(author, 0) + tweet["retweets"]
          authors[author] = authors.get(author, 0) + 1
  
      # Plot the tweet authors
      plt.xlabel('Tweet Authors')
      plt.ylabel('Number of tweets')
      plt.title('Tweet Author Summary')
      plt.bar(authors.keys(), authors.values())
      plt.show()
  
      # Plot the number of likes
      plt.xlabel('Tweet Authors')
      plt.ylabel('Number of Likes')
      plt.title('Number of Likes Summary')
      plt.bar(likes.keys(), likes.values())
      plt.show()
  
      # Plot the number of retweets
      plt.xlabel('Tweet Authors')
      plt.ylabel('Number of Retweets')
      plt.title('Number of Retweets Summary')
      plt.bar(retweets.keys(), retweets.values())
      plt.show()
  
output:     
      # Plot the tweet authors
      plt.xlabel('Tweet Authors')
      plt.ylabel('Number of tweets')
      plt.title('Tweet Author Summary')
      plt.bar(authors.keys(), authors.values())
      plt.show()
  
      # Plot the number of likes
      plt.xlabel('Tweet Authors')
      plt.ylabel('Number of Likes')
      plt.title('Number of Likes Summary')
      plt.bar(likes.keys(), likes.values())
      plt.show()
  
      # Plot the number of retweets
      plt.xlabel('Tweet Authors')
      plt.ylabel('Number of Retweets')
      plt.title('Number of Retweets Summary')
      plt.bar(retweets.keys(), retweets.values())
      plt.show()
  