code: def apply(self,word,ctx=None):
          
          chars = get_letters(word)
          flag = True #no error assumed
          reason = None #no reason
          prev_letter = None
          for char in chars:
              if prev_letter == char:
                  flag = False
                  break
              prev_letter = char # continue loop
          if not flag:
              reason = RepeatedLetters.reason
          return flag,reason
docs: ignore ctx information right now