input: from typing import List
  
  def remove_punctuation_special_chars_stopwords(tweet: str) -> List[str]:
      """This function reads in a tweet and removes all punctuation, special characters, and stopwords.
      >>> remove_punctuation_special_chars_stopwords("I'm so excited to be going to the #MuseumTour! #BigDay #travel")
      ['excited', 'going', 'MuseumTour', 'BigDay', 'travel']
      """
      import re
      import string
      from nltk.corpus import stopwords
  
      tweet_clean = re.sub(r'[^\w\s]','',tweet) #remove punctuation
      tokens = tweet_clean.split() #split string into individual words 
      stop_words = set(stopwords.words("english")) #get list of stopwords
      filtered_tokens = [w for w in tokens if not w in stop_words] #remove stopwords
      return filtered_tokens
output:     import re
      import string
      from nltk.corpus import stopwords
  
      tweet_clean = re.sub(r'[^\w\s]','',tweet) #remove punctuation
      tokens = tweet_clean.split() #split string into individual words 
      stop_words = set(stopwords.words("english")) #get list of stopwords
      filtered_tokens = [w for w in tokens if not w in stop_words] #remove stopwords
      return filtered_tokens