code: def get_datetime_string(datetime_obj):
          '''
          Get datetime string from datetime object
  
          :param datetime datetime_obj: datetime object
          :return: datetime string
          :rtype: str
          '''
  
          if isinstance(datetime_obj, datetime):
              dft = DTFormat()
              return datetime_obj.strftime(dft.datetime_format)
  
          return Nonf get_datetime_string(datetime_obj):
          '''
          Get datetime string from datetime object
  
          :param datetime datetime_obj: datetime object
          :return: datetime string
          :rtype: str
          '''
  
          if isinstance(datetime_obj, datetime):
              dft = DTFormat()
              return datetime_obj.strftime(dft.datetime_format)
  
          return None
docs: Get datetime string from datetime object
  
          :param datetime datetime_obj: datetime object
          :return: datetime string
          :rtype: str