code: def get_build_logs(self, build_id, follow=False, build_json=None, wait_if_missing=False,
                         decode=False):
          
          logs = self.os.logs(build_id, follow=follow, build_json=build_json,
                              wait_if_missing=wait_if_missing)
  
          if decode and isinstance(logs, GeneratorType):
              return self._decode_build_logs_generator(logs)
  
          # str or None returned from self.os.logs()
          if decode and logs is not None:
              logs = logs.decode("utf-8").rstrip()
  
          return logs
docs: provide logs from build
  
          NOTE: Since atomic-reactor 1.6.25, logs are always in UTF-8, so if
          asked to decode, we assume that is the encoding in use. Otherwise, we
          return the bytes exactly as they came from the container.
  
          :param build_id: str
          :param follow: bool, fetch logs as they come?
          :param build_json: dict, to save one get-build query
          :param wait_if_missing: bool, if build doesn't exist, wait
          :param decode: bool, whether or not to decode logs as utf-8
          :return: None, bytes, or iterable of bytes