input: Write a function to implement an autocomplete system that predicts words based on the input text. If the input text is empty, return an empty list.
  assert autocomplete("")==[]
  assert autocomplete("hel")==["help", "hello", "helm", "helpful", "helmet"]
  assert autocomplete("pro")==["program", "project", "process", "produce", "product"]
  assert autocomplete("so")==["solve", "solution", "software", "source", "social"]
output: def autocomplete(text):
      words = ["help", "hello", "helm", "helpful", "helmet", "program", "project", "process", "produce", "product", "solve", "solution", "software", "source", "social"]
      return [word for word in words if word.startswith(text)]