input: Write a function to read in a tweet and remove all punctuation, special characters, and stopwords. The function should return the cleaned tweet as a list of words. If the input tweet is empty, the function should return an empty list.
  assert remove_punctuation_stopwords("I'm so excited to be going to the #MuseumTour! #BigDay #travel")==['excited', 'going', 'MuseumTour', 'BigDay', 'travel']
  assert remove_punctuation_stopwords("")==[]
output: def remove_punctuation_stopwords(tweet):
      import string
      from nltk.corpus import stopwords
      stop_words = set(stopwords.words('english'))
      translator = str.maketrans('', '', string.punctuation)
      words = tweet.translate(translator).split()
      cleaned_words = [word for word in words if word.lower() not in stop_words]
      return cleaned_words