input: from typing import List, Tuple
  
  def reverse_words(sentence: str) -> str:
      """
      Reverse the order of words in a given sentence while keeping the order of characters in each word the same.
      
      Example:
      >>> reverse_words('This is a sentence.')
      'sentence. a is This'
      >>> reverse_words('Python is a programming language.')
      'language. programming a is Python'
      """
      words = sentence.split(" ")
      reversed_words = words[::-1]
      return ' '.join(reversed_words)
output:     words = sentence.split(" ")
      reversed_words = words[::-1]
      return ' '.join(reversed_words)