input: Write a python function to analyze sentiment score of a sentence using nltk's SentimentIntensityAnalyzer.
  assert analyze_sentiment("The food here is terrible and the service is even worse.") == -0.8345
  assert analyze_sentiment("I love this place, the food is amazing!") == 0.6696
  assert analyze_sentiment("It's an okay place, nothing special.") == 0.0
output: def analyze_sentiment(sentence):
      from nltk.sentiment import SentimentIntensityAnalyzer
      sia = SentimentIntensityAnalyzer()
      score = sia.polarity_scores(sentence)['compound']
      return score