input: Write a function to develop an autocomplete system that predicts words based on the input text. The function should generate word candidates from the input text, filter them, rank the top 5 words, and return them.
  def autocomplete(input_text):
      # 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]
  
  assert autocomplete("hel")==["hello", "help", "hell", "helmet", "helm"]
  assert autocomplete("pro")==["program", "problem", "process", "production", "project"]
  assert autocomplete("fin")==["find", "final", "finger", "finding", "finale"]
  assert autocomplete("java")==["java", "javascript", "jar", "javadoc", "javelin"]
  assert autocomplete("")==["the", "and", "or", "a", "in"]
output: def autocomplete(input_text):
      word_candidates = generate_candidates(input_text)
      filtered_words = filter_candidates(word_candidates)
      sorted_words = rank_words(filtered_words)
      return sorted_words[:5]