input: Write a function to check if a given string contains all the words in a provided list of words. If the string contains all the words, return True; otherwise, return False.
  def contains_words(input_string, words):
   for word in words:
   if word not in input_string:
   return False
   return True
  
  assert contains_words('This is a test', ['test', 'this', 'is'])==True
  assert contains_words('Hello World', ['World', 'Hello'])==True
  assert contains_words('Python Programming', ['Ruby', 'Java'])==False
  assert contains_words('Quick brown fox', ['fox', 'dog'])==False
  assert contains_words('', [''])==False
output: def contains_words(input_string, words):
      for word in words:
          if word.lower() not in input_string.lower():
              return False
      return True