code: def strftime(self, format):
          
  
          output = self._format(format)
          if py2:
              return output.encode('utf-8')
          return output
docs: Formats the date using strftime()
  
          :param format:
              The strftime() format string
  
          :return:
              The formatted date as a unicode string in Python 3 and a byte
              string in Python 2