input: Write a function to take in two strings as input and output a list of all the words in both strings. Return the list of words after splitting each string into its individual words.
  def string_to_list(s1, s2):
      s1_list = s1.split()
      s2_list = s2.split()
      output_list = s1_list + s2_list
      return output_list
  
  assert string_to_list("I want to make a difference", "The journey to success is long") == ['I', 'want', 'to', 'make', 'a', 'difference', 'The', 'journey', 'to', 'success', 'is', 'long']
  assert string_to_list("programming is fun", "python is awesome") == ['programming', 'is', 'fun', 'python', 'is', 'awesome']
  assert string_to_list("", "python") == ['python']
  assert string_to_list("test cases", "") == ['test', 'cases']
  assert string_to_list("", "") == []
output: def string_to_list(s1, s2):
      s1_list = s1.split()
      s2_list = s2.split()
      output_list = s1_list + s2_list
      return output_list