input: def autocomplete(input_text: str) -> List[str]:
      """Provides autocomplete suggestions for given input text based on some predefined rules.
  
      The function generates word candidates from the input text, filters them, and then ranks 
      them to give the top 5 suggestions.
  
      >>> autocomplete("app")
      ['apple', 'application', 'apples', 'appliance', 'appreciate']
  
      >>> autocomplete("ba")
      ['balance', 'ball', 'bank', 'base', 'basket']
  
      >>> autocomplete("z")
      ['zone', 'zip', 'zoom', 'zero', 'zone']
      """
      
      # Generate the word candidates
      word_candidates = generate_candidates(input_text)
      # Filter the word candidates 
      filtered_words = filter_candidates(word_candidates)
      # Rank the words and return the top 5 
      sorted_words = rank_words(filtered_words)
      return sorted_words[:5]
output:     def generate_candidates(input_text: str) -> List[str]:
          # Example implementation: generate candidates by adding common suffixes
          suffixes = ['', 'e', 's', 'ing', 'ed', 'ly', 'er', 'est', 'able', 'ible', 'al', 'ial', 'ic', 'ive', 'ize', 'ise']
          return [input_text + suffix for suffix in suffixes]
  
      def filter_candidates(candidates: List[str]) -> List[str]:
          # Example implementation: filter out words that are not in a predefined dictionary
          dictionary = {'apple', 'application', 'apples', 'appliance', 'appreciate', 'balance', 'ball', 'bank', 'base', 'basket', 'zone', 'zip', 'zoom', 'zero'}
          return [word for word in candidates if word in dictionary]
  
      def rank_words(words: List[str]) -> List[str]:
          # Example implementation: rank words by length and then alphabetically
          return sorted(words, key=lambda x: (len(x), x))