input: Write a python function to check if a given text is a question.
  assert is_question("Is this a question?") == True
  assert is_question("This is not a question.") == False
  assert is_question("What time is it?") == True
  assert is_question("No, it's not.") == False
output: def is_question(text):
      return text.strip().endswith('?')