input: 
  from typing import List
  
  
  def analyze_sentiment(text: str) -> str:
      """ Categorize given text into positive, negative, or neutral sentiments.
      >>> analyze_sentiment("I really enjoyed the movie.")
      'positive'
      >>> analyze_sentiment("I didn't like the ending at all.")
      'negative'
      >>> analyze_sentiment("It was a decent movie.")
      'neutral'
      """
  
output:     positive_words = ["enjoyed", "good", "great", "excellent", "happy"]
      negative_words = ["didn't like", "bad", "terrible", "disappointed", "sad"]
      
      text_lower = text.lower()
      
      for word in positive_words:
          if word in text_lower:
              return 'positive'
      
      for word in negative_words:
          if word in text_lower:
              return 'negative'
      
      return 'neutral'